The document discusses the importance of monitoring cloud-hosted applications to manage availability and performance risks, emphasizing the need for proactive detection of issues, alerts, and data collection. It outlines various types of monitoring tools and techniques, including application, server, and end-user monitoring, as well as the significance of log aggregation and cloud analytics. The document also highlights the evolution towards holistic monitoring solutions that integrate multiple monitoring levels and the pitfalls of relying solely on custom application logging.

1. Monitoring your cloud-hosted app
18/07/2012
Andreas Chatzakis
@achatzakis on twitter
AWS Usergroup Greece

2. whoami
Andreas Chatzakis
 CTO & co-founder /
 High traffic Greek Real Estate portal
 Software delivery team management
 IT Operations
 co-founder of AWS Usergroup Greece
@achatzakis
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3. Why monitoring
You need monitoring to proact or react to
availability & performance risks and issues:
 Detect problems before (many) users are aware
 Alerts and notifications at 3 AM
 Be informed of issues you wouldn't be able to recreate
 Collect data to discover root cause of an incident
...and automate response for next time
 Statistics and KPIs to track service quality trends
 Visibility to prioritize optimization efforts
 Make sense out of large quantity of logs and data
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4. Monitoring in the cloud
Principles are not that diverse from
traditional infrastructure but...
 Cloud allows us to build highly dynamic setups
 More data
 Our tools need to adapt
 Ephemeral resources require centralized approach
 Need aggregation based on server role
 Cloud promises agility
 Only possible when cost of failure is low
 Being able to spot issues in a more automated
manner is key
 The rise of the devops
 Developers need visibility to understand how their
code affects costs and impacts availability
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5. Types of monitoring
There is a variety of monitoring tools that
complement each other
 External checks (is my app still up?)
 Server monitoring (CPU, RAM, IO...)
 Systems monitoring (mySQL, Apache etc metrics)
 Process monitoring (restart crashed services)
 Application monitoring (bottlenecks in the code)
 End user monitoring (client side performance)
 Log aggregation & analysis (centralize storage)
 Cloud Analytics (do I make the most out of AWS?)
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6. Deployment models
Consider the deployment model of each
monitoring solution
 Agent vs Agent-less
 SaaS vs DIY on own computing instances
 Consider different AZ or provider
 Least privilege principle (e.g. read-only
access to agent)
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7. Pricing models
Different pricing models offered by the
various solutions
 Freeware
 Per host
 Per host-hour
 Per user
 Per alert
 Per stored Gbyte
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8. External tests
External tests detect failure & alert you so
that you react
 Treats your app as a black box
 Periodic check from a bot
 Define expected response (specific string)
 Tests from different geographies
 Report on average response time, latency etc
 Alert via email, sms, phone
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9. Server & Systems monitoring
Server monitoring collects data from OS and
Systems
 Server metrics (CPU, Load Average, RAM, IO activity)
 System metrics (Apache status, MySQL connections...)
 Typically works via an agent or remote access
 Can point towards root cause
 But can't trace issues to specific parts of your code
 Helps with capacity planning and scaling decisions
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10. Process monitoring
Processes die or misbehave... Monitor their
health and automate response
 Tools that check critical processes
 Restart if crashed process
...or those using too many resources
 Can configure complex scenarios
 Beware of false positives
 Beware of recurring restarts
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11. Application monitoring
A 'Flight recorder' for your code helps you
fix real issues.
 It is often hard to recreate a production issue.
 Plugs into your app servers & tracks execution
 Code tracing
 Captures errors, input variables and debugging
info
 Records performance metrics
 Time spent on DB, Cache, external services
 Overhead of specific classes or methods
 Slow queries
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12. End user monitoring
Get real data about the experience of your
app's users
 It works for you. Does it work for them?
 Servers running ok. What about that 3rd party widget?
 Typically collects actual end user data via js
 Capture performance issues faced by user segments
 OS / browser / addons
 Network connection speed
 Geographical location
 First time visit VS warm browser cache
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13. Log aggregators
Centralized storage of logs for cloud setups
with ephemeral instances
 Logs are sent over to centralized repository
 Persists after server has been decomissioned
 Logs are captured, stored, archived & recycled
 Logs are indexed and analyzed
 Preconfigured analyzers for known apps
 Free text analyzers for less known apps
 Alerts based on specific patterns, frequencies
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14. Swiss knives
The future might belong to holistic
monitoring solutions
 Monitoring at multiple levels
 Correlating data can be a godsend for
devops
 Cloud management tools might move to
integrate or provide such functionality
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15. A common pitfall
While it does have its uses, you should not
rely on custom application logging
 Typically inconsistent logging that is added
reactively
 Developer bias and lack of operational
issues understanding
 logging what you anticipate to go wrong
 Increased code maintenance costs and risks
 Can hurt performance if you are not careful
 Instead use a proper monitoring toolset
 let developers focus on building new
functionality
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16. Cloud Analytics
Combine traditinal monitoring with Newvem's
Analytics and make the most of the cloud
 Powerful analytics of cloud usage data
 Reveal security & availability issues in
your cloud infra
 Get actionable insights
 Identify opportunities for cost reductions
 Spot overloaded resources requiring
vertical or horizontal scaling
 Visibility and confidence you making the
most of the cloud
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18. Questions
?
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