Note to Presenter: Present to customers and prospects to provide them with an overview of EMC PowerPath Viewer.
One of the business challenges in many of today’s data centers is to manage a growing number of hosts. Even in data centers where PowerPath is used, monitoring the storage infrastructure gets to be very complex as the number of hosts increases. The PowerPath “powermt display”CLI command provides specific information that helps users trying to identify and isolate infrastructure and array issues. However, it can be tedious to issue this command on each individual host, when there are tens or maybe even hundreds of hosts in the data center.
The chart on this slide shows that initiatives aimed at cost reduction and business process improvement remain the top two initiatives, with business process improvement which includes moving mission-critical applications into production virtual environments taking on more importance relative to cost reduction initiatives. This is in sync with the server virtualization revolution, which is designed to reduce both CAPEX and OPEX; server virtualization requires fewer physical resources and maintenance and licensing costs are generally lower. As server virtualization environments continue to mature, organizations will virtualize more and more mission-critical production workloads and demand tighter integration and cross-functional, virtualization-aware monitoring and management tools to provide a simple, consolidated view of activity across the data center.
PowerPath’s value fundamentally comes from its architecture and position in the I/O stack. PowerPath sits above the Host Bus Adapter allowing heterogeneous support of operating systems and storage arrays. By integrating with the I/O drivers, all I/Os run through PowerPath and allow for it to be a single I/O control and management point. Finally as shown here, PowerPath also sits below the application level, database level, and file system level. This combination allows it to be an infrastructure manageability and control point. This allows PowerPath to work with any raw devices, volume manager, or file system, and to be the basis for path management rather than just multipathing. Automates multipathing policies including failover and recovery—to provide enhanced control, eliminating cumbersome manual I/O load balancing that is time consuming and less than exact. Standardize path management. PowerPath applies the same tool set across operating systems and patented algorithms across physical and virtual environments to reduce the number of tools necessary to optimize data paths. Scale-out mission-critical applications . PowerPath not only assures better application availability, in many implementations, it can have a substantial impact on I/O throughput and overall application performance.
PowerPath Viewer is a free utility that provides centralized, remote monitoring of your PowerPath-managed storage environment. PowerPath Viewer comprises two main components: It provides a consolidated display of events and allows you to view and monitor up to 500 PowerPath hosts through a graphical user interface (GUI). You can view hosts, host groups, LUNs, individual paths to each LUN, and buses. All host discovery that takes place within PowerPath Viewer Console is for viewing and monitoring within PowerPath Viewer only. Any host group that you may create within PowerPath Viewer Console does not affect the storage configuration within the hosts themselves. So you cannot manage/administer your PowerPath Hosts from the PowerPath Viewer, only monitor those hosts. The information displayed in PowerPath Viewer Console is similar to the information that is displayed when you run the powermt display PowerPath command. It is also similar to the information found in the PowerPath GUI console on Windows. PowerPath Viewer Console presents the information in windows and panes, called Views.
PowerPath Viewer provides a great solution for easily monitoring configurable “alerts” for hundreds of PowerPath Hosts. This utility accepts the type of data normally shown with the powermt display command from each monitored PowerPath host and displays the consolidated information on a centralized management station. Users can see the big picture for their storage infrastructure, or drill down for details. Information is displayed in a user friendly GUI. From a single console, users can easily keep track of path, bus and LUN events for each PowerPath host. Any changes in the Path state can be included in an email so that an administrator is notified. This tool provides clear business benefits as less time and fewer resources are required to monitor a complex storage infrastructure. PowerPath Viewer is ECUE-compliant (EMC Common User Experience) meaning it has the same look and feel as other EMC software management tools.
There are two components required for PowerPath Viewer to operate. The first component is the PowerPath Management Component that runs on each PowerPath host that you wish to monitor. PowerPath Management Component is the means through which the remote hosts that you wish to monitor and PowerPath Viewer Console communicate. The Management Component is bundled with PowerPath on the following platforms; Windows, Linux, Solaris, and HP-UX. For AIX, the Management Component is located on Powerlink as a separate download. The Management Component is not required for PowerPath/VE for VMware vSphere because the PowerPath Viewer Console communicates with the remote VMware vSphere host on which PowerPath is installed through the CIMOM (Common Information Model Object Manager) and communicates via the Message Passing API (MP API). You must discover the PowerPath/VE VMware vSphere hosts through a similar discovery process as for PowerPath hosts. Instead of a heartbeat, Viewer polls the VMware vSphere host to check for device status change. The Management Component listens for kernel events from the PowerPath driver, sends alerts to the Console over IP, and listens for commands from the Console, among other tasks. The second required component is the Java-based PowerPath Viewer Console that consolidates all of the PowerPath hosts information and displays it in a user-friendly GUI. The GUI is ECUE compliant and has the same look and feel as other EMC management software tools. The Viewer Console and remotely managed PowerPath hosts communicate over IP. Neither a Fibre Channel, iSCSI, nor an FCoE connection is required for communication. PowerPath Viewer Console also alerts you to any changes in status to PowerPath devices through two monitors: the Path Alert Monitor, for changes in the status of physical data paths between hosts and individual LUNs; and the Bus Alert Monitor, for changes in the status of SAN connections between hosts and arrays. A TCP/IP network provides the link between the PowerPath hosts and the PowerPath Viewer Console.
The Viewer Console is supported on Windows 7 or Windows Server 2008R2, physical or virtual. The supported architectures are X86 or X64.
In the current version, the PowerPath Viewer can monitor up to 500 hosts. Each newly installed PowerPath Viewer Console must be configured to discover its own PowerPath hosts.
The console architecture allows a single PowerPath hosts to be monitored by a maximum of five PowerPath Viewer Consoles today.
Minimum system requirements for the PowerPath Viewer Console to monitor are listed here. PowerPath Viewer is currently supported for Windows hosts with PowerPath v5.3 and later. EMC does not recommend running the PowerPath Viewer Console on any host running PowerPath. Any arrays qualified to work with PowerPath v5.3 and later are qualified for PowerPath Viewer. See the E-Lab Interoperability Navigator, available on Powerlink, for current up-to-date information
The PowerPath Management Component is an agent software component that runs on Windows and Linux today. The Management Component is not required for PowerPath/VE for VMware vSphere. Instead, the PowerPath Viewer Console communicates with the remote VMware vSphere host on which PowerPath is installed through the CIMOM (Common Information Model Object Manager). You must discover the PowerPath/VE VMware vSphere hosts through a similar discovery process as for PowerPath hosts. Instead of a heartbeat, Viewer polls the VMware vSphere host to check for device status change. The bottom of the table on this screen lists all the various versions of PowerPath that are supported. Note. PowerPath Viewer is not supported with PowerPath Migration Enabler.
The PowerPath Viewer Console is very easy to install. Download the PowerPath Viewer package on the Support section of the Powerlink website as shown on the slide. No reboot of the Windows system is required after the Console is installed.
Starting with the following platforms/versions of PowerPath, the Management Component is included with the PowerPath multipathing software package and does not require a separate installation: PowerPath 5.5 for Solaris and later PowerPath 5.2 for HP-UX and later PowerPath 5.7 for Linux and later
You can change the Port number or Heartbeat interval parameters during installation of the Management Component, or by running the change option on the installation procedure. The default and recommended port for the Management Component is port 9083. Valid alternative port range is 49152–65535. The heartbeat interval value is the amount of time in minutes that the Management Component communicates with the Viewer to verify it’s connection. The default value is 10 minutes. If there are many PowerPath managed hosts on the network, they could generate more IP traffic. So, a customer may decide to increase the heartbeat interval as the number of hosts increase. If there are network issues, it might be beneficial to reduce the value to below 10 minutes to try and debug the situation.
For Unix, the configuration file needs to be edited after the Management Component is installed. To enable the Management Component on Unix, a 1 is entered at the prompt. To modify the heartbeat interval, a 2 is entered at the prompt. Then a prompt message will display requesting a heartbeat interval level. The valid range in minutes is 1–60 To modify the port number, type a 3 at the prompt. Then type the number of the desired port. The default and recommended port number is 9083. The valid range is 49152–65535. After all changes are made, enter 13 to confirm and save the file. Then start the new agent. Type: > /etc/init.d/emcp_mond.sh
The PowerPath Management Component has two tasks to perform to enable PowerPath Viewer. The first task is to listen for PowerPath events, such as “path dead“ and “path alive” events that are reported by the PowerPath driver. These are the same PowerPath events that are seen in the system log, and have always been reported by the PowerPath driver. The second task is to communicate with the PowerPath Viewer Console. This communication is bidirectional using Secure Socket Layer (SSL) protocol for security. Data is transmitted in a proprietary XML format. Events are collected and sent to the PowerPath Viewer Console as alerts. If no events have occurred, a heartbeat is sent according to the heartbeat interval setting. Installation of the PowerPath Management Component does not require a reboot, and there is no I/O disruption. If you are installing on a Windows host, ensure that you have administrative privileges on the host on which you are installing PowerPath Management Component. Non-administrative users cannot enable PowerPath Management Component. • If you are installing on a Linux host, ensure that you have root privileges on the host on which you are installing PowerPath Management Component. • Ensure that PowerPath is installed on all the hosts on which you plan to install PowerPath Viewer Management Component. • Ensure that you have a properly configured DNS environment. Successful discovery of your remote hosts on PowerPath Viewer using the IP address and hostname requires a properly configured DNS environment. PowerPath Viewer returns a host discovery failure if provided an IP address or hostname resulting from an improperly configured DNS environment. • Determine the TCP port that you will assign to PowerPath Viewer. The default and recommended port is 9083; the valid, alternative port range is 49152–65535. • If there is a firewall between PowerPath Viewer and the remote PowerPath host, open the TCP port on your firewall that you have assigned to PowerPath Viewer in the previous step. Note that TCP port connections are initiated by PowerPath Viewer Console and remain open while the Console is managing the remote host. • If you are installing on a Windows host and you are using the CLI silent installation method, ensure that you create the log file directory before beginning the installation. The CLI silent installation fails without any indication of error if the log file directory does not exist prior to installation.
The PowerPath Management Component of the PowerPath Service is an enhancement that allows PowerPath to send data to the remote PowerPath Viewer Console on Windows environments, in addition to its previous tasks of supporting SNMP and the Local Windows PowerPath Monitor. The PowerPath Management Component links with the PowerPath multipathing library (via MPAPI –Multi-Path Application Programmer Interface) to listen for events or request current path states from the PowerPath driver. If there is a change in path status, then an alert is sent to the PowerPath Viewer Console. Otherwise, heartbeat data is sent every 10 minutes (the default heartbeat interval). PowerPath Viewer is interoperable with PowerPath Management Pack for Microsoft Operations Manager (MOM). You do not need to re-install or reconfigure MOM in order to install and configure the PowerPath Management Component.
Before a PowerPath host can send information to the PowerPath Viewer Console, it must be discovered. During discovery the PowerPath Management Component accepts the connection request from the PowerPath Viewer Console. The PowerPath Management Component registers with the PowerPath driver for path and bus events. It then listens for these events. When an event occurs, the Management Component processes them and puts them into an XML message. The XML message is sent to the PowerPath Viewer Console as an asynchronous alert. The Management Component also listens for and responds to commands from the Console. If there are no events to report, the PowerPath Management Component stays in contact with the PowerPath Viewer Console through heartbeat XML messages. The default is to send a heartbeat message every 10 minutes. The heartbeat not only ensures that the socket connection between the Management Component and the Console is good, but it verifies that the PowerPath Management Component can get events from the PowerPath driver. NOTE: The default heartbeat value is 10 minutes. It is user configurable on the host and can be between 1 and 60 minutes.
How does the PowerPath Management Component process PowerPath events? Sometimes there can be a burst of hundreds of path events. To avoid sending an XML alert for each event and overwhelming the PowerPath Viewer Console, the PowerPath Management Component queues the path events until there is a three second pause. When no path events have occurred for three seconds, the Management Component processes them by fetching the event details (including path, volume and host information), from the PowerPath driver via MPAPI, and creating an XML summary alert indicating a change in the PowerPath host status. The XML alert is sent as an unsolicited summary message to the PowerPath Viewer Console. There are actually two monitors, one for path events and one for bus events. Path events are processed by the path event monitor to produce summary alerts. Bus events, which are less common, are processed by the bus event monitor to produce bus alerts. If there has been no PowerPath path event or bus event during the 10 minute heartbeat interval, then the Management Component uses MPAPI to get a full report and send a summary alert at the end of the interval.
The PowerPath Management Component also listens for commands from the Console. Once the Management Component has accepted an incoming connection request from the Console, it listens for and responds to XML formatted commands. Each command has an associated ID so that if there are multiple Consoles, each recognizes responses to the commands it has issued. Query commands are sent by the Console to request path and volume information. These may require the PowerPath Management Component to get information from the PowerPath Driver. There are three different XML formatted responses that may be dispatched to the Console. They are “summary,” “summary rescan,” and “path details.” The “summary” response sends a copy of the most recent summary alert. The “summary rescan” and “path details” responses call the MPAPI to get the current data. Information obtained through MPAPI is formatted into an XML response and sent to the Console.
As mentioned previously, there is no Management Component for PowerPath/VE for VMware. PowerPath Viewer Console communicates with the remote VMware vSphere host on which PowerPath is installed through the CIMOM (Common Information Model Object Manager) and communicates via the Message Passing API (MP API). You must discover the PowerPath/VE VMware vSphere hosts through a similar discovery process as for PowerPath hosts. Instead of a heartbeat, Viewer polls the VMware vSphere host to check for device status changes.
As mentioned earlier, the information displayed in PowerPath Viewer Console is similar to the information that is displayed when you run the powermt display command as seen above. The powermt display command displays information about HBAs or devices configured for and managed by PowerPath. Here is a review of the command and the meanings of the displayed values. Storage_system_type logical device count (Symmetrix logical device count = 9) = the total number of unique logical devices from all storage devices of a given type that are configured by PowerPath and that this host can access. The maximum value is platform-specific. Host Bus Adapters ### - Represents the PowerPath number for the HBA. When the dev option is used, the output of powermt display identifies the HBA by this same HBA number. This number is preserved across boots but is not preserved after configuration changes. Host Bus Adapters HW Path Windows: port#\\path#, where # is the integer displayed in Properties in Disk Administrator or Disk Management; for example, port1\\path0. UNIX: Operating-system-specific hardware descriptive name for the bus: AIX: The name of the device that is the parent of the hdisk; for example, scsi1. HP-UX: Hardware path as defined by the ioscan command; for example, 10/4.2.0. Solaris: Modification of the /dev/rdsk symbolic link target; for example, sbus@1f,0/fcaw@3,0. Linux: HBA name registered by the HBA driver, for example, lpfc. I/O Paths Summary - Status of the paths originating from this HBA: • optimal means all paths are alive (usable). • degraded means one or more, but not all, paths from this HBA are dead (not usable). • failed means all paths are dead and no data is passing through this HBA. I/O Paths Total - Total number of paths that originate from this HBA. In the example above, there are a total of 9 paths from the HBA. The maximum number of logical devices supported by one HBA is platform specific. The total number of paths may exceed the number of logical devices in a complex SAN topology, due to zoning. I/O Paths Dead - Total number of paths originating from this HBA that are dead (not usable). Stats IO/sec - This field is blank for powermt display, unless it is used with the “every” parameter. Subsequent powermt display iterations display the average number of I/Os sent across this bus each second. Stats Q-Ios - Total number of outstanding I/Os on this HBA now. Stats Errors – Total number of times this path transitioned from alive to dead. This is always equal to or less than the total number of HBA I/O path errors. Note that the error count may be different for different LUNs using the same physical paths.
The powermt display dev=harddisk6 command displays information about the specified device. Again, this information is captured in the PowerPath Viewer Console. Here is an explanation of the fields displayed. Pseudo name - Platform-specific value assigned by PowerPath to the PowerPath device. storage_system_type ID - Identification number for the storage system on which the logical device is located. Logical device ID - Identification number for the logical device. Each logical device on each storage system has a unique ID. Each storage system, however, uses the same storage-system ID. Together, storage-system ID and logical-device ID create a unique ID for every logical device in the world. State - State of the PowerPath device can be the following: Dead or Alive. Policy - Current load-balancing and failover policy for the device. In the example above it is SymmOpt, which is optimized for Symmetrix. See PowerPath documentation for other policy types. Queued- Ios - Number of I/O requests queued to this PowerPath device. Host ### - PowerPath number for the HBA. Host HW Path : Windows: port#\\path#\\tgt#\\lun#, where # is the integer displayed in Properties in Disk Administrator or Disk Management. For example, port2\\path0\\tgt6\\lun7. (A LUN, or Logical Unit Number, is a logical device.) UNIX: The platform-specific hardware descriptive name for the path: AIX: The name of the device that is the parent of the hdisk; for example, fscsi1. HP-UX: Hardware path as defined by the ioscan command; for example, 10/4.2.0. Solaris: Modification of the /dev/rdsk symbolic link larger. Linux: HBA name registered by the HBA driver. Registration of the HBA name is optional Host I/O Path - The platform-specific device name for the path. Stor Interf . – Storage-system interface. For Symmetrix systems, this has three parts: - Interface type: Fibre Channel (FA) - Interface address: integer in the range 1 to 16 - Interface port: [abcd][AB] For VNX OE and CLARiiON systems, this has one part: Interface port: SP [A-B][0-3] I/O Paths Mode - Current path mode: Active indicates this path can accept I/O. Load balancing is performed for a device with more than one active path, based on the load-balancing and failover policy set for the device. Standby indicates this path is held in reserve. Being set to standby does not mean a path will not be used. It only means the weight of the path is heavily adjusted to preclude its use in normal operations. Unlic indicates that unlicensed PowerPath is running for a storage system (no license key has been installed). In this scenario, all paths are marked unlicensed except one path to each SP. Unlicensed paths cannot become candidates for path failover. I/O Paths State – Current path state: Alive indicates the path is usable: PowerPath can direct I/O to this path. Dead indicates the path is not usable: PowerPath will not direct I/O to this path. After marking the path dead and incrementing the Errors count, PowerPath tests the path to see whether it is usable. If the test succeeds, PowerPath marks the path alive; the path is then available for I/O. If the test fails, the path remains dead, and PowerPath ignores it for subsequent I/O operations. If all the paths to a logical device are dead, PowerPath retests each path Stats Q-Ios - Total number of I/O operations under way to this path. This is the total number of I/O requests to this device that have not completed. The sum of in-progress I/Os for all paths should equal the number of in-progress I/Os for the PowerPath device. Stats Errors - Total number of times this path transitioned from alive to dead. This is always equal to or less than the total number of HBA
There will be discussions further in this presentation that talk about BUS and Path testing and status. Let’s stop for a moment and discuss the terminology used by PowerPath. A BUS refers to two connected SAN edge points (for example, Fibre Channel fabric N-port addresses) in the storage configuration: an HBA port on the server on one end and an storage port on the other. The HBA is the initiator (I) and the storage port is the target (T). This differs from a storage path, which refers to a host's end-to-end storage connection with an LU. Typically, multiple storage paths traverse a single BUS. As a result, a BUS failure is usually accompanied by multiple storage path failures.
A path refers to the physical route between a host and a storage system Logical Unit (LU). This includes the host bus adapter (HBA) port, cables, a switch, a storage system interface and port, and an LU. LU refers to a physical or virtual device addressable as a single storage volume behind a storage system target. So, in the example above, the HBA is the initiator (I), the storage port is the target (T) and the LUN is (L).
Going a bit more in-depth, as already mentioned, PowerPath automates data path diagnostics behind the scenes—and applies the same analytics to bus testing. PowerPath continually works to determine the operational status and viability of a data path—while always insulating applications from the path and bus testing routines. Testing is adaptive to the load place on the host servers to ensure no impact on application availability and performance. Path tests are scheduled with a lower priority than application I/O. Paths are activated and de-activated based on the success or failure of these tests.
The main PowerPath Viewer Host Monitor views are shown here. The screen is divided into three parts: the Host View, Host BUS View, and Host LUN View.
The Preferences icon is used for selecting the display language (currently only English is available), managing emails and other PowerPath settings. This will be covered in more detail in the next slide.
The General tab allows you to set PowerPath Viewer interface language and to set a debug level. The General tab contains the following fields: Field Description Language English; default and only language available currently. UI Debug Log Level User interface problem debugging. The UI Debug Log drop-down list contains the following levels: UI Debug Log Level Description Severe Indicates an error that impacts the functionality of PowerPath Viewer caused by unexpected exceptions, errors in the communications protocol, memory allocation problems, and crashes. Warning Indicates a problem caused by mistakes in the information you have entered. Is the default setting. Error Indicates an error that you can correct. None Indicates that no problem debug log level is set. Information N/A (these last options are place holders and not currently implemented) Debug N/A Timer N/A None N/A
The Settings tab allows you to configure the polling interval for PowerPath/VE hosts, interval for re-establishing lost connections, and other settings between PowerPath Viewer and PowerPath Management Service. The Settings tab contains the following fields: Field Description VMWare vSphere Polling Interval (mins): Setting for PowerPath Viewer to poll vSphere hosts for device status changes. Is user-configurable from 1 to 60 minutes. Default is 10. Attempt to re-establish lost connection every (mins): Setting for PowerPath Viewer to attempt to reconnect when a host loses connection. Is user-configurable from 1 to 60 minutes. Default is 10. vSphere port timeout (millisec): Setting for PowerPath Viewer Console to wait before t timeout to establish a connection during vSphere host discovery. Is user-configurable from 500 to 10,000 milliseconds. Default is 500. Path Alert Auto-Cancel: Setting for PowerPath Viewer Path Alert Monitor to decrement alerts for events when they are resolved or to continue incrementing alerts. Default is Disabled. Bus Alert Auto-Cancel: Setting for PowerPath Viewer Bus Alert Monitor to increment alerts for events when they are resolved or to continue incrementing alerts. Default is Disabled. Restore Default Settings Resets any configuration setting that has a default value to its default value.
PowerPath Viewer can be configured to send an email to a designated account when an alert is detected. To do this, click on the Preferences icon (red box in top right-hand corner). Then select the Manage Email tab. The PowerPath Viewer Console can be configured to wait a specific amount of time and consolidate alerts before sending an email, as seen here. Field Description Send Email on Alert Option to select if you want PowerPath Viewer to send emails when an alert is received. If selected, Host Views shows Email Alert: ON in bottom-left of Host View Window. Consolidate Email Option to select if you want PowerPath Viewer to consolidate email messages in the case that several emails are generated by the same failure. Consolidate Interval (minutes to wait before send) The interval in minutes that PowerPath Viewer waits to consolidate and send email when an alert is received unless the maximum number of alerts is collected. Default value is 10; valid range is 1-60. Maximum number of Alerts per Email The maximum number of alerts that PowerPath Viewer will collect before sending an email irrespective of the consolidation interval. Default value is 300; valid range is 2-1000. Protocol Email protocol for PowerPath Viewer. Can be SMTP or SMTPS. SMTPS uses SSL for enhanced security. Send Alerts To (comma separated list) List of email addresses to which the alerts are sent. Separate all entries with a comma. Required field. Email Sent From Email address that shows in From: field in the email alert. Required field. Outgoing Mail (SMTP or SMTPS) Server IP address or hostname of the SMTP server of the outgoing email address. Required field. Port Number SMTP or SMTPS server port number. Default is 25 (recommended). Port number is user-configurable with a valid alternative range of 49152-65535. Required field. Use SMTP Authentication Option to select if outgoing SMTP server requires authentication for email notifications. Account Name: User ID to outgoing SMTP your server. Required only with SMTP authentication. Your full email address (including @your_domain.com) Password The password to outgoing SMTP server. Required only with SMTP authentication. Test Email Settings Option to select if you want to send tests emails to addresses entered in the Manage Email fields. Test Email Results Results from test carried out in Test Email Settings. Restore Default Settings Resets any configuration setting that has a default value to its default value.
Once emails are enabled, you’ll see that Email Alert On is indicated at the bottom, left-hand corner of the main Console Menu/screen. If a critical icon appears at the bottom of the screen by the email information, that indicates that the email has not been delivered. You must resolve the email delivery issue and receive a successful email delivery message in the Test Email Results field of Preferences.
Email notifications will be sent to the administrator's inbox as shown here. When the email is opened, the administrator will find a brief description of the issue.
Use the Logout & Exit icon to exit PowerPath Viewer console.
The Help Icon is used to open context sensitive help (online help). There is only online help and Release Notes for PowerPath Viewer. There are no user guides for PowerPath Viewer.
In the Host View window, one of the first/basic tasks is to discover and manage hosts and host groups within PowerPath Viewer. The Host Group/Host column displays the name of the PowerPath host group. A host group is a group of PowerPath hosts that are gathered together for organizing within PowerPath Viewer only. PowerPath is the default host group that exists upon launching PowerPath Viewer for the first time. When expanded, name of the PowerPath host. The hostname is not assigned through PowerPath Viewer or through the PowerPath Viewer discovery process. When you change the hostname or IP address, you may need to delete and rediscover the host. The Path column displays the state of LUNs in the PowerPath host group. The Setup column shows the condition/health of failover policy; that is, whether the host group or host is operating in an optimal failover policy for its licensed state, the state of paths to LUNs in the PowerPath host group, and/or the condition/health of path-to-LUN configuration ratio. The OS column displays the Operating system running on the PowerPath hosts within the host group. The Version column, displays the version and build of PowerPath running on the PowerPath hosts within the host group. On the right side of this screen are the icons you see displayed in the Host View and their meaning: Represents the PowerPath host group within PowerPath Viewer. When collapsed, the “worst” status of any hosts is displayed to ensure that more critical events are not masked. PowerPath/VE virtual host; that is, VMware vSphere host. PowerPath physical host; that is, Windows, Linux, AIX, Solaris, or HP-UX host.
When the cursor lands on an icon in the Path or Setup columns, a Tooltips box will appear providing more information on the error/icon to help debug an issue. For instance, the Empty Group indicates that there is a Host Group with no PowerPath hosts configured/assigned to it. <Click to advance slide> The next screen indicates that the PowerPath host does not have a license installed on it. <Click to advance slide> And finally, the last screen indicates that there are some paths that are dead.
The basic tasks for organizing Views and windows include: Expanding/collapsing tree tables Filtering information displays Exporting information Help Let’s take a look at each of these features in the Host View window. The Expands All/Collapse All icon is used to expand or collapses tables in the Host View window.
The filter function in PowerPath Viewer is similar to an advanced search. PowerPath Viewer matches the text that is typed in the Filter for field first by columns that are searchable by text. Columns that have icons associated with them are not searchable. Then PowerPath Viewer matches by additional criteria that you may select in the Filter for drop-down list. PowerPath Viewer filters out rows that do not contain the text specified in the Filter for field by the criteria selected in the drop-down list, leaving in the View only those rows that contain matches for the selected text and other selected criteria. To further limit your search, select one of the supported wildcard options: A question mark (?) An asterisk (*) A plus sign (+) These filter criteria exist for all the Host View, the Host Bus View, and the Host LUN View. The Host View contains another set of filter criteria related to the status of the PowerPath-managed hosts, paths, and policy. The criteria are: All (default) Setup Error Setup Warning Path Error Path Warning These filters criteria filter at the level chosen and any levels beyond the level chosen. For example, if you filter by Path Warning in the drop-down list, rows with hosts experiencing both path warning and path failure remain in Host View. Note that there is limited combining of two types of filter criteria. If you search the Host View by the status-related filter criteria, you can use only the text Filter for option. Any options that you may have selected in the Filter for drop-down list are automatically erased. For example, if both Linux and Microsoft hosts are experiencing path failures, you can filter only Linux hosts experiencing path failure using the filtering feature.
The export function in PowerPath Viewer provides the ability to export information to a Comma Separate Value file (.csv). The Excel spreadsheet is an example of an exported file in CSV format. This can be useful for managing PowerPath hosts, and a view in time of the configuration when you are monitoring several hundred hosts with PowerPath Viewer.
The Help Icon is used to open context sensitive help (online help). There is only online help and Release Notes for PowerPath Viewer. There are no user guides for PowerPath Viewer.
In the Host View window, there is a popup menu that will display when you right click in the window. The Refresh option is used to refresh host data. Some changes do not trigger immediate alerts in PowerPath Viewer. For an immediate update on the refresh, you can use the popup menu. Some of these scenarios that do not refresh immediately in the Viewer include: Load-balancing policy changes Adding or removing devices Paths changing modes (Active, Standby, Unlic) Although it may appear that PowerPath Viewer is not refreshing or updating the host data when you right-click and select Refresh, EMC does not recommend repeatedly and successively refreshing host data. There is a slight overhead and delay associated with recollecting data from the host. Repeatedly clicking Refresh causes the process to start again and thus causes more of a delay in reflecting the updated host data. Other options on the Popup Menu include the ability to: Create a New Group Rename a Group Delete Host(s) Delete Group(s) Update Credentials NOTE: You can update vSphere credentials after host discovery in the case that you lose the host connection due to a change in vSphere credentials. To update credentials, right-click on a vSphere host. The vSphere Authentication window appears. Enter the correct vSphere username and password credentials for PowerPath Viewer to remain connected to the vSphere host. The Update Credential option is only available for vSphere.
The basic tasks for discovering and managing hosts and host groups within PowerPath Viewer include: Discovering hosts in PowerPath Viewer Creating host groups in PowerPath Viewer Adding/moving hosts to host groups in PowerPath Viewer Removing hosts from host groups in PowerPath Viewer Removing hosts from PowerPath Viewer The Discover Hosts button on the bottom begins the process of discovering host that will be viewed within PowerPath Viewer. It is important to note that all host discovery and management that takes place within PowerPath Viewer is for viewing and monitoring within PowerPath Viewer only. You cannot install PowerPath on a host using PowerPath Viewer. Any host group that you may create within PowerPath Viewer does not affect the storage configuration within the hosts themselves. The Host Discovery Wizard is the step-by-step process that PowerPath Viewer uses to discover PowerPath hosts for viewing and monitoring. When PowerPath Viewer discovers PowerPath hosts, it goes through a process of recognizing hosts that PowerPath already manages on the network. You cannot install PowerPath on a host by using PowerPath Viewer. The discovery process is slightly different for PowerPath hosts than for PowerPath/VE vSphere hosts. PowerPath/VE discovery for vSphere hosts requires authentication before discovery can be finalized. Authentication credentials include the administrator username and password
The Connection Type window displays. The PowerPath/VE for Windows Hyper-V and PowerPath radio button is used to discover Windows, Linux and Hyper-V hosts. And the PowerPath/VE for VMware vSphere radio button is used to discover vSphere hosts . The PowerPath /VE for Windows and PowerPath radio button is used to discover Windows and Linux hosts. The PowerPath/VE for VMware vSphere radio button is used to discover PowerPath on an vSphere hosts. In the future, the radio button will include HPUX, AIX and Solaris. For the radio button, PowerPath/VE for Windows and PowerPath, the Port Number field displays the default TCP port number of 9083. It is recommended to leave the default TCP port number. If that port number is already being used, you can change it. The valid alternative range is 49152-65535. For the radio button, PowerPath/VE for VMware vSphere, the Port Number field defaults to port number 5989. The port number is not user-configurable for vSphere hosts.
After Next is clicked from the previous screen, the Search Range Window will appear. The IP Address(s) or Host Name(s) radio button is where IP addresses or Host names can be entered for the wizard to discover. Separate multiple IP addresses or hostnames with a comma. The input files can be a mix of hostnames and ip addresses. Alternatively, you can type the IP address range (you should type the IP address subnet range.)
Alternatively, the Read CSV (comma separated values) File button can be pressed and a file containing the IP addresses or Host Names separated by commas can be read in. An Open File window will appear to allow navigation to the location of the CSV file. The IP addresses are then filled in under the radio button: IP Address(s) or Host Name(s) radio button (10.241.230.20, etc). The Read CSV File feature reads hostnames from a .txt file that is stored on your host and automatically populates the hostnames contained in the .txt file. The Read CSV File feature facilitates discovery of the same PowerPath remote hosts and host groups on several hosts by reducing the amount of manual entry of hostnames for PowerPath Viewer host discovery. Instead of retyping the hostnames each time you'd like to discover them on a different remote host, the Read CSV File feature reads the hostnames or IP addresses from the .txt file and populates them for you.
After the Next button is clicked, the Group Selection Window displays to allow the user to select the Group to add the host to. In addition, you have the option to create a new group name.
After the Next button is clicked, the Discovered Hosts Results window will appear and a scan is performed to begin identifying the hosts and the current state of hosts. Host - The PowerPath host that is being discovered for viewing within PowerPath Viewer. State - Identifies the state of discovery. The states are: Connected: The host is connected to a host Management Service. No Response on Port: Nothing is listening on the remote port. Pending: The discovery attempt is pending. PowerPath was removed: vSphere only. PowerPath has been removed from the vSphere host. Requires Authentication: vSphere only. You must login before monitoring. Already Monitored: The host associated with the IP address/hostname is already discovered and monitored by PowerPath Viewer. Connecting: The discovery attempt is connecting to the remote host. DNS Lookup Failed: The host associated with the IP address/hostname could not be reached on the network. Maximum Connections Exceeded: The remote host has rejected the discovery attempt because it is already connected to the maximum number of PowerPath Viewer Consoles. Connection Failed: The connection cannot be established because PowerPath Viewer is unable to connect to remote port; the incorrect TCP port was specified during the discovery. Connection Closed: The remote connection is closed because the incorrect TCP port was specified during the discovery. Canceled: The connection request was canceled because Cancel was clicked Once the scan progresses to 100%, the Discover Host process is finished.
By default, there is one Host Group folder called PowerPath. You can monitor all of your PowerPath hosts from this one folder. However, users with a lot of PowerPath hosts to monitor will probably want to organize their hosts into user-defined groups. For example you may want to group your hosts by the applications they run, or some other criteria. Then with a quick glance at the Host View screen, you can check the status of an entire group. Expanding the group folder will let you check the status of individual hosts within the group. To add hosts to a group, click on the group folder and click Discover Hosts or after you add the group, drag and drop the currently discovered host into the group. The PowerPath Discovery Wizard starts and allows you to specify the host IP addresses or host names you want to include in the group. If you use the Read CSV File feature to discover your hosts, EMC recommends creating one .txt CSV file for each PowerPath Viewer host group that you intend to create. There is no documented limit to the number of Groups that can be created.
The Remove button in the Host View allows you to select the group, host or hosts that you want to remove from PowerPath Viewer. To remove multiple hosts to the host group, press the Control key while selecting the desired hosts. The PowerPath Group cannot be deleted nor removed from the Viewer.
Icons are used in the Path and Setup columns to give a quick summary of the state of each monitored PowerPath host. Let’s explore the meaning of the icons in each column.
In the Host View window, a Ok icon in the Path indicates the following: At the Host Level: All LUNS are accessible All Paths are alive At the Host Group Level: All hosts are responding. All LUNs are operational; there is full I/O access on all LUNs. All host paths are alive. As you can see in the slide above, all of the LUNs have full access and all 13 of the paths are alive.
In the Host View window, an Unknown icon in the Path indicates the following: At the Host Level: No LUN information is available. No path information is available. PowerPath/VE host is unlicensed or unregistered. Applies to PowerPath/VE VMware vSphere hosts only. At the Host Group Level the unknown icon would indicate that one or more hosts are not reporting. As you can see in the slide above, the PowerPath/VE host is not licensed.
In the Host View window, a Warning icon in the Path indicates the following: At the Host Level: All LUNs are accessible but there is degraded LUN I/O access One or more paths are dead No LUNs are configured. At the Host Group Level: All hosts are responding One or more hosts have degraded LUN I/O access As you can see in the slide above, 91 out 94 paths are alive. So, three paths in the configuration on host lppa012 are dead.
A Critical icon in the Path indicates the following: At the Host Level: One or more LUNs are not accessible At the Host Group Level: One or more hosts have no LUN I/O access As you can see in the slide above, host lppa015 has no paths to its LUNs.
In the Host View window, an OK icon in the Setup column indicates the following: At the Host Level: Host is connected to PowerPath Viewer Heartbeat is coming from PowerPath hosts PowerPath host running optimal load-balancing policy All paths are configuration compliant (for example, more than one path is configured to the LUN) At the Host Group Level: All hosts are OK with respect to Setup
In the Host View window, when the Setup column displays the Unknown icon it can indicate the following: At the Host Level: PowerPath host is not responding to TCP connection attempts. At the Host Group level: One or more hosts are not responding All other hosts are OK or in a Warning state with respect to Setup. As you can see in the slide above, the RHEL host has a communication problem to the array.
In the Host View window, when the Setup column displays the Warning icon it can indicate the following: At the Host Level: PowerPath/VE license expires within 15 days. Applies to PowerPath/VE VMware vSphere hosts only. No LUNs are configured. At the Host Group level: One or more hosts are in a Warning state with respect to Setup As you can see in the slide above, host Lppa025 has no LUNs configured.
In the Host View window, when the Setup column displays the Critical icon it can indicate the following: At the Host Level: One or more hosts have an error with respect to Setup : PowerPath or PowerPath/VE host is unlicensed or unregistered or license is expired. No PowerPath or Needs Login. Applies to PowerPath/VE VMware vSphere hosts only. PowerPath host is running BasicFailover or NoRedirect policy. Only one path is configured to the LUN. Only one path is accessible to one or more LUNs, its other paths having failed. At the Host Group level: One or more hosts are in a Critical state with respect to Setup As you can see in the slide above, host lppa018 only has a single path configured.
The Host Bus View provides HBA-to-array port status in the context of a single host's storage path set. The Host Bus View gives you an aggregate view of the selected host's storage paths that are affected by a dead HBA port, array port, or switch port. Multiple hosts' Bus Views can be correlated to aid root cause analysis of many types of equipment faults within a SAN. The Host Bus View provides the high-level view of your storage configuration. The Host Bus View gives you insight into paths and LUNs that might be affected by the dead HBA port or array port. You can use that information to analyze affected paths and LUNs in the Host LUN View. It is important to note that PowerPath Viewer is not switch-aware. That means that if a switch in the storage configuration becomes degraded, although the Host Bus View shows a warning and sends an alert or email (if configured), the dead switch itself does not appear in the Host Bus View. If the dead switch is on the back end of the HBA port, it appears as an HBA port warning. If the dead switch is on the back end of the array port, it appears as an array port warning. This can cause confusion because upon investigation in your storage configuration, the HBA ports and array ports in the affected bus may in fact be alive. Furthermore, even when an array port is dead, it does not display as dead in PowerPath Viewer but rather as degraded. This is because there is no way to determine in PowerPath Viewer that it is an array port failure and not an array port-side switch failure. The height and width of the Host Bus View are adjustable.
The following table lists the Host Bus View columns:
In the Host Bus View, the Expand All/Collapse All icon will expand or collapse tables. When the table is expanded, information in the Array Name and Array Port columns are displayed. At the bottom, right hand corner of the screen, it shows the number of items (20) displayed. Once the table is collapsed, the Array Name and Port information disappears.
The filter function in PowerPath Viewer is similar to an advanced search. PowerPath Viewer matches the text that is typed in the Filter for field first by columns that are searchable by text. Columns that have icons associated with them are not searchable. Then PowerPath Viewer matches by additional criteria that you may select in the Filter for drop-down list. Like the Host View icons, there is also an Export file and Help icons in the Host Bus view.
In the BUS View window, an OK icon in the HBA Port column indicates that a ll paths through the HBA port are alive.
In the BUS View window, a Warning icon in the HBA Port column indicates that there is a problem with an Initiator or Target.
In the BUS View window, a Critical icon in the HBA Port column indicates that there is a problem with an Initiator or Target. For instance, maybe all paths through the HBA port are dead.
In the BUS View window, an OK icon in the Array Port column indicates that a ll paths through the array port are alive.
In the BUS View window, a Warning icon in the Array Port column indicates that there is a problem with an Initiator or Target.
The Host LUN View allows you to monitor the LUNs and paths in your storage configuration. The Host LUN View provides a view and status of the individual paths between the HBA and the LUNs of the currently selected host. When you click and highlight a host in the Host View, that host's path and LUN information become available in the Host LUN View. LUNs are displayed in the LUN View by the name that is being used. If the PowerPath pseudo name assigned to the LUN name is being used, that is how the LUN is displayed in the Host LUN View. The icon to the left of the LUN name indicates the status of the LUN. You can click the node to the left of the icon to display the paths in the LUN's path set, if you are using the pseudo device. If you are using the native device, the paths represent individual paths to the LUN. The icons to the left of the path names indicate the status of the path. If you no longer want to display the individual paths to each LUN, click the node to the left of LUN icon to hide them. The height and width of the Host LUN View are adjustable.
The following table lists the Host LUN View columns:
The filter function/icon in the Host LUN view works similar to the Host View window. However, there are more filter options available for a LUN view due to all the LUN view columns available. The LUN View contains a similar, more limited set of filter criteria related to the status of the PowerPath-managed LUNs. The criteria are: All (default) LUN Warning LUN Failure Like the Host View icons, there is also an Export file and Help icons in the Host LUN view.
In the LUN View window, an OK icon in the Name column indicates the following: When node is collapsed, all known paths are alive to the LUN. When node is expanded, path is alive to the LUN.
In the LUN View window, a Warning icon in the Name column indicates that o ne or more paths are dead to the LUN. On this screen, we see that HBA Port 6 is dead.
The Host View window (on the left) displays a critical icon in the Path column indicating some of the LUNS do not have access. The Bus View window (top right) displays a critical icon in the HBA Port column indicating that there is a problem with an Initiator or Target. To determine which ports are dead, you need to go to the LUN View window (bottom right) and see which port is effected. <click mouse to bring up next screen> In the LUN View, when you expand the LUN name, you can see that the issue is with HBA Port #6. This port has become disabled/dead and as an administrator, you know where you need to go to fix the problem. In the LUN View window, a Critical icon in the Name column indicates the following: When node is collapsed, all paths are dead to the LUN. When LUN node is expanded, path is dead to LUN. These are not recommended configurations. On this screen we see that the name is Critical because HBA Port 6 is dead for those LUN names.
In the LUN View window, a Critical icon in the Live/Total Paths column indicates that only one path is configured to LUN. This is not a recommended configuration.
In the LUN View window, a Critical icon in the Policy column indicates that Basic Failover or No Redirect policy is in effect on path. This is not an optimal load-balancing policy because it means that load balancing is not in effect. Basic Failover is not supported on vSphere. I/O routing on failure is limited to one HBA and one port on each storage system interface. When a host boots, it designates one path (through one interface) for all I/O. If an I/O is issued to a logical device that cannot be reached via that path (that is, the I/O cannot reach that logical device through the device's assigned interface), the logical device is assigned to the other interface. This policy protects against VNX OE and CLARiiON SP failures, Symmetrix FA port failures, and back-end failures, and it allows non-disruptive upgrades to work when running PowerPath without a license key. It does not protect against HBA failures. This policy is the default policy without a PowerPath license for EMC storage arrays. The proper way of installing/configuring PowerPath is: Run the Configuration Checker application first to ensure that the host is configured to the hardware and software required for PowerPath multipathing features as specified in the EMC Support Matrix. Install and configure PowerPath Install and Configure PowerPath Viewer to ensure that what you’ve installed is working properly. Until you go into the Viewer, you may think that your configuration/installation is working/configured properly until you see that Policy in the Host LUN view has a critical setting.
In the LUN View, an unlicensed icon indicates the Power Path is unlicensed. This issue is resolved by adding a valid PowerPath license to the host.
When the Host View receives a warning or critical icon in the Path column, as shown here for lppa015.lss.emc.com, the administrator, can go to the Path Alerts and Bus Alerts tab at the top of the screen to get more information. Path and Bus alerts are not stored in a database. The console must be running to capture this information.
The Path Alert Monitor allows you to view and monitor any alerts that PowerPath Viewer has detected with respect to paths and LUNs. You can configure PowerPath Viewer to send emails when PowerPath Viewer detects alerts. An alert is a message from the host that indicates that a change or transition has occurred. This information is not stored anywhere and only captured when the Viewer is running. It does not store any historical information. In the example above, the warning under Severity indicates that on the host (lppa015) , out of the 8 paths, 4 paths are dead. That could indicate that one of the HBA’s is dead.
The following table lists the Path Alert Monitor columns:
The Bus Alert Monitor allows you to view and monitor any alerts that PowerPath Viewer has detected with respect to the bus; that is, the HBA and array ports. You can configure PowerPath Viewer to send emails when PowerPath Viewer detects alerts. An alert is a message from the host that indicates that a change or transition has occurred. This information is not stored anywhere and only captured when the Viewer is running. It does not store any historical information. On the Bus Alert tab in this window, the critical icon indicates that Bus is dead; the HBA is not communicating with the array port.
The following table lists the Bus Alerts Monitor columns:
Once the issue is resolved, the Bus Alerts tab displays an Informational icon. This indicates that any previously dead paths have been restored. The Alert Count maintains the count that incremented when the bus went dead even after the bus is restored, unless you have Auto-cancel enabled.