OpenSSH is a suite of network connectivity tools that replace telnet, ftp, rsh, and rcp. It encrypts all traffic including passwords. There are two main components - the OpenSSH server (sshd daemon) and OpenSSH client commands (ssh, sftp, scp). The server and client configurations are controlled by configuration files that specify options like encryption, authentication methods, and port forwarding. Host-based authentication allows connecting from trusted hosts without passwords by using public keys stored on both the client and server systems. TCP port forwarding through an SSH connection can redirect network traffic through an encrypted tunnel, allowing secure access to services like HTTP from outside a firewall.
Here, you can learn all information about Shell Script.
1. What is Shell Script?
2. Types of Shell Script.
3. Use of Shell Script.
4. Command line of Shell Script.
5. Example of Shell Script.
전체목차: https://netpple.github.io/docs/make-container-without-docker/
클라우드 위에서 컨테이너에 가상 IP를 부여하고 이러한 가상 IP대역을 기반으로 컨테이너 간에 통신이 어떻게 가능한 것일까요?
동적으로 오버레이 네트워크를 구성해 봅니다.
지난 시간 가상IP 대역을 기반으로 서로 다른 물리노드 간의 통신을 가능하기 위하여 가상 디바이스를 생성하고 ARP cache와 Bridge FDB 정보를 입력해주고, vxlan 기반의 UDP encapsulation과 터널링을 통하여 가상디바이스의 L2정보를 목적지 노드로 전송하여 통신이 되는 것을 확인하였습니다.
이에 대한 내용을 바탕으로 가상네트워크를 추가하고 통신할 때 커널 이벤트(NETLINK)를 캐치하여 동적으로 arp, fdb 갱신처리하여 컨테이너 간에 통신이 가능하도록 구성해 봅니다.
Here, you can learn all information about Shell Script.
1. What is Shell Script?
2. Types of Shell Script.
3. Use of Shell Script.
4. Command line of Shell Script.
5. Example of Shell Script.
전체목차: https://netpple.github.io/docs/make-container-without-docker/
클라우드 위에서 컨테이너에 가상 IP를 부여하고 이러한 가상 IP대역을 기반으로 컨테이너 간에 통신이 어떻게 가능한 것일까요?
동적으로 오버레이 네트워크를 구성해 봅니다.
지난 시간 가상IP 대역을 기반으로 서로 다른 물리노드 간의 통신을 가능하기 위하여 가상 디바이스를 생성하고 ARP cache와 Bridge FDB 정보를 입력해주고, vxlan 기반의 UDP encapsulation과 터널링을 통하여 가상디바이스의 L2정보를 목적지 노드로 전송하여 통신이 되는 것을 확인하였습니다.
이에 대한 내용을 바탕으로 가상네트워크를 추가하고 통신할 때 커널 이벤트(NETLINK)를 캐치하여 동적으로 arp, fdb 갱신처리하여 컨테이너 간에 통신이 가능하도록 구성해 봅니다.
Using Secure Shell on Linux: What Everyone Should KnowNovell
Secure Shell, or SSH, is a network protocol that allows data to be exchanged over a secure channel. SSH is much more than just data being passed over the wire. SSH can be used to tunnel traffic and specific ports or applications across multiple servers. SSH is a must for anyone using Linux. If you haven't used SSH, then you have not used Linux!
This session is designed for all technical staff or decision makers curious about great Linux tools and making access to Windows services, remote desktops and remote servers easier and less complicated. During this session, we will demonstrate techniques to tunnel RDP sessions, SOAP sessions and HTTP sessions between remote systems.
install hadoop in windows using maven and windows sdk and visual c++ compiler.
To install hadoop on windows see below link step by step guidance.
From version 2.3 hadoop suppot windows also but by default it supports linux and other version. to install in windows need to compile the hadoop source in native windows sdk and then that hadoop distribution generated can be used to run hadoop in windows.
hadoop installation on windows
Melbourne Infracoders: Compliance as Code with InSpecMatt Ray
Presentation to the Melbourne Infrastructure Coders Meetup November 8, 2016. Overview of InSpec (https://inspec.io) and the idea of "Compliance as Code"
http://www.meetup.com/Infrastructure-Coders/events/233990769/
Internal knowledge share on SSH setup and usage. Includes some helpful config file options to save time and how to create and use SSH keys for better security and productivity.
OpenSSH is a FREE version of the SSH connectivity tools that technical users of the Internet rely on.
This talk will explain the most interesting features of ssh and some info about future developments.
This slide is special for master students (MIBS & MIFB) in UUM. Also useful for readers who are interested in the topic of contemporary Islamic banking.
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
Biological screening of herbal drugs: Introduction and Need for
Phyto-Pharmacological Screening, New Strategies for evaluating
Natural Products, In vitro evaluation techniques for Antioxidants, Antimicrobial and Anticancer drugs. In vivo evaluation techniques
for Anti-inflammatory, Antiulcer, Anticancer, Wound healing, Antidiabetic, Hepatoprotective, Cardio protective, Diuretics and
Antifertility, Toxicity studies as per OECD guidelines
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
Francesca Gottschalk - How can education support child empowerment.pptxEduSkills OECD
Francesca Gottschalk from the OECD’s Centre for Educational Research and Innovation presents at the Ask an Expert Webinar: How can education support child empowerment?
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...Dr. Vinod Kumar Kanvaria
Exploiting Artificial Intelligence for Empowering Researchers and Faculty,
International FDP on Fundamentals of Research in Social Sciences
at Integral University, Lucknow, 06.06.2024
By Dr. Vinod Kumar Kanvaria
1. OpenSSH Quick Reference Protocol SSH protocol 2, 1 NumberOfPasswordPro
mpts
Allow the number of password
tries
3
Author: Jialong He StrictModes check files ownership and perm. yes
Jialong_he@bigfoot.com SyslogFacility Syslog facility code AUTH
http://www.bigfoot.com/~jialong_he TCPKeepAlive Send TCP keepalive to other end yes
TCPKeepAlive Send TCP keepalive to client yes
VerifyHostKeyDNS Verify the remote key using DNS no
UseDNS lookup client DNSname yes
What is OpenSSH and where to get it CheckHostIP Check the host IP address in the yes
Compression Compress network traffic yes known_hosts file
OpenSSH is a protocol suite of network connectivity tools that replace
telnet, ftp, rsh, and rcp. It encrypts all traffic (including passwords) to X11Forwading Permit X11 forwarding no
effectively eliminate eavesdropping, connection hijacking, and other
network-level attacks. OpenSSH comes with most Linux distributions. Public Key Authentication
Use command “ssh -V” to check the SSH version installed. The latest
Client Configuration Public key authentication is a preferred method. It is more secure than
password authentication because no password travels through the network,
version can be found from: www.openssh.org ssh (sftp, scp) are OpenSSH commands to replace telnet, ftp, rcp. The
but you have to do some setup before you can use public key
properties of these program are controlled by (1) command line options,
authentication. Public key authentication is configured for individual user.
Server Configuration (2) per user configuration file $HOME/.ssh/config and (3) system wide
configuration file /etc/ssh/ssh_config.
sshd is the OpenSSH server (daemon). It is controlled by a configuration (1) Modify SSH server’s configuration file (sshd_config) to enable public
file sshd_config which normally resides in /etc/ssh directory. You can key authentication: (PublicKeyAuthentication yes). Also modify client’s
Usage Example:
specify command-line options to override their configuration file configuration file (ssh_config) to use public key authentication
ssh user@remotehost # connect to remote host as user
equivalents. Here are some useful options. For the complete list of (PubkeyAuthentication yes). Normally, these are default settings.
scp myfile user@remotehost:/home/user # remote copy “myfile”
keywords, see sshd_config (5) manual page.
(2) Generate a key pair for this user
Keyword Description Default Here are useful keywords in ssh_config. For the complete list of keywords,
ssh-keygen –t rsa –f $HOME/.ssh/id_rsa
see ssh_config (5) manual page.
AllowGroups Allow only specified groups to *
connect. May use '*' and '?'. Keyword Description Default It will prompt you a passphrase to encrypt private key. Two files “id_rsa”
Default host to connect none and “id_rsa.pub” will be generated.
AllowUsers Allow only specified users to * HostName
connect. May use '*' and '?'. User Default user name none (3) Transfer user’s public key (id_rsa.pub) to SSH server and append its
DenyGroups Groups NOT allowed connecting. none PreferredAuthentications Preferred authentication methods see left contents to:
hostbased, publickey, password $HOME/.ssh/authorized_keys or $HOME/.ssh/authorized_keys2.
DenyUsers Users NOT allowed connecting. none
AllowTcpForwarding TCP forwarding allowed. yes HostbasedAuthentication Try hostbased authentication no You may also restrict from which computers allowed to use public key
PubkeyAuthentication Try Public key authentication yes authentication. For example, in authorized_key file, you put “from” before
GatewayPorts Allow other computers to connect no
the public key.
to the forwarding port. PasswordAuthentication Try password authentication yes from=”Goat.domain.com” AAAAB3NzaC1yc2EAAA ….
HostbasedAuthentication Allow host based authentication no LocalForward Specify TCP port forwarding in none
(use .shosts or /etc/shosts.equiv) LPORT RHOST:RPORT (4) Now you can log on to remote system with
ssh my_sshserver
IgnoreRhosts Ignore per user .rhosts and .shosts yes RemoteForward Remote forward port none
in hostbased authentication. RPORT LHOST:LPORT It will prompt you passphrase to decrypt the private key. If you did not
IgnoreUserKnownHosts Ignore $HOME/.ssh/known_hosts, no GatewayPorts Allow hosts other than this host to no give a passphrase in the step 2, you will be connected with asking
use only /etc/ssh/ssh_known_hosts connect to the forwarding port password.
PasswordAuthentication Password authentication allowed yes ForwardX11 Forward X11 connection no (5) If you do give a passphrase to protect private key, but don’t want to
PermitEmptyPasswords Allow blank password no Compression Compress network traffic no type this passphrase every time, it is possible to use ssh agent command:
PublicKeyAuthentication Public key authentication allowed yes CompressionLevel If use compress, compress level 6 eval `ssh-agent`
AuthorizedKeysFile Public key file name. Default: see left ssh-add ~/.ssh/id_isa
$HOME/.ssh/authorized_keys Port Default remote port 22
This will prompt you passphrase once. As long as the current terminal is
ListenAddress IP address to accept connection 0.0.0.0 Protocol SSH protocol 2, 1 open, you can connect to the SSH server without typing passphrase. Note,
Port Listening port 22 StrictHostKeyChecking Allow connect to a host which is ask this is only valid for the current terminal, you still need to type passphrase
LogLevel sshd verbosity level info not in $HOME/.ssh/known_hosts in other terminal.
or /etc/ssh/ssh_known_hosts
PermitRootLogin Allow root login yes In order to run scripts without typing password, the easiest way is to use a
LogLevel Verbosity level info blank passphrase in step 2. Unlike password, passphrase never travels
PrintLastLog Print last login date yes
through the network. It is used for protecting local private key.
PrintMotd Print /etc/motd file yes
2. Host-based Authentication TCP Port Forwarding
Hosted based authentication can be useful to run batch files or scripts on OpenSSH can forward TCP traffic through SSH connection and secure
remote computers. It is very tricky to configure host based authentication. TCP applications such as POP3, IMAP or HTTP by direct clear text TCP
Even if you follow the instructions exactly, you might still get a password traffic through SSH (tunneling). Port forwarding can also redirect some
prompt. In this case, double check file permissions (.shosts) and computer TCP traffics through firewall.
names (must use FQDN). Restart computer (in order to have sshd read
configuration file). In order to use port forwarding, you must first establish SSH connection
and the connection must stay on as long as forwarding needed. In other
words, you have to logon on to SSH server. There are two kinds of port
Server Side forwarding: local and remote forwarding
(1) Modify /etc/ssh/sshd_config to enable host based authentication:
HostbasedAuthentication yes
Local Forwarding
IgnoreRhosts no
In local forwarding, application servers (e.g., mail server) are on the same
IgnoreUserKnownHosts no # optional
computer as the SSH server. For example, suppose we have a server named
RhostsAuthentication yes # optional, not recommended
“horse” and it has web and SSH servers running. On another computer
named “goat”, using following command forwards traffic to an arbitrarily
Let SSH daemon to re-read configuration file by either reboot the
chose port (here 12345) on “goat” to port 80 on “horse”,
computer or send “kill –HUP /var/run/sshd.pid”. On Redhat Linux, you
can restart SSH daemon using: service sshd restart
ssh –g –L 12345:horse:80 horse
(2) Copy client’s public key to the SSH server. Client’s public key usually
If you point a web browser to http://goat:12345, it will show the contents
stored in /etc/ssh/ssh_host_rsa_key.pub on client computer.
of http://horse. Here “-g” means that other hosts can access this forwarding
port (here 12345). Similarly, you can forward other TCP traffic (e.g., POP3
If client also has OpenSSH server running, you can fetch its public key by:
110, IMAP 143) through SSH tunnel.
ssh-keyscan –t rsa client_FQDN > /etc/ssh/ssh_known_hosts2
If per user known hosts is enabled (IgnoreUserKnownHosts no), you Remote Forwarding
connect to the client’s SSH daemon from the server, the client’s host key
will be saved in: $HOME/.ssh/known_hosts If your application server is on the same machine as SSH client (i.e., you
run SSH client on the application server), you should use remote
Note: You MUST use FQDN of client computer to get its public key. forwarding. For example, we have a server named “horse” and client
Following files are used to store client’s public key on the server. named “goat”. On “horse”, you run
System wide: Per user:
ssh –R 12345:horst:80 goat
/etc/ssh/ssh_known_hosts $HOME/.ssh/known_hosts
/etc/ssh/ssh_known_hosts2 $HOME/.ssh/known_hosts2
You can point your web browser to http://goat:12345, it will show the
content as if you accessed http://horse. This time, you can only access port
(3) Add client’s FQDN in $HOME/.shosts. Please note the permissions for “12345” on “goat” (no Gateway port).
this file must be owned by the user and NOT writable by group/others.
If (RhostsAuthentication yes), you can also use /etc/hosts.equiv,
but this is NOT recommended. Besides, it has NO effect for root login.
Client Side
(1) Enable host based authentication in SSH client configuration file:
/etc/ssh/ssh_config
HostbasedAuthentication yes
(2) You should have RSA host key pair (normally in /etc/ssh)
ssh_host_rsa_key
ssh_host_rsa_key.pub
If not, generate key pair with:
ssh-keygen –t rsa –f /etc/ssh/ssh_host_rsa_key –N “”