GNS3 couldn’t run /usr/bin/dumpcap in child process: Permission Denied.

Ubuntu 16.04 LTS GNS3: Problem: couldn’t run /usr/bin/dumpcap in child process: Permission Denied. Solution: 1- Enable non-root user to capture network traffic by reconfiguring wireshark. gns3a@gns3A:~$ sudo dpkg-reconfigure wireshark-common 2- Add wireshark group to the user that you want to start GNS3 program. gns3a@gns3A:~$ sudo gpasswd -a $USER wireshark 3- Logout and Login again.   […]

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VMware Hot-Add RAM on Rhel 5

Last week, I  confronted a problem. Even though virtual guest which is rhel5.11(Tikanga) enabled for hot-add RAM, It did not update the new memory size,  after adding 4 GBs of RAM without power off the machine. Solution: Finally, I have found the solution. We need to apply some couple of commands to hit the kernel […]

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SOCKS

SOCKS stands for Socket Secure. It exchanges data packets between client and server via proxy. It operates on the Session Layer of the OSI model. It allows users to surf on the Internet anonymously. More than that It gives you accessibility of applications only one secure port connection. In this post, I will implement fundamental […]

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Sample Expect Script

Expect is a programming language for automating systems which expose interactive text terminal such as telnet, ssh, ftp, scp etc,. It is extension to Tcl language. It is created by Don Libes. In this post I will share you sample expect script, which connects list of servers over ssh, executes command and prints it out […]

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Screen & Rsync

Screen: Default key binding Ctrl+a d: Detach screen from this terminal. Ctrl+a r: Reattach a session and if necessary detach it first. screen -ls : Lists existing screen sessions. To reattach session you have to know session id.

screen -r <session id>

Rsync: To send a file with rsync over ssh protocol(ssh key); […]

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Connect to Real World With GNS3

GNS3 is a GPL licenced cross-platform network simulation program. It enables us both virtual and physical networks operate together. It emulates Cisco IOS, doing so we have real Cisco device capability in a Virtual Machine. You can also analyze the packets with Wireshark. One exception that GNS3 has limited device capability as some Cisco devices impossible […]

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