SSH or git-clone via Proxy

SSH or git-clone via Proxy
Today we were setting up few Web servers on a private network which will be serving the traffic through the Load Balancer. The setup was simple until we came to know that the Webservers needs to connect to github.com for the repository access.   Diagnosis We have a jumpbox / Bastion (10.10.1.10) which is used for ...

Jenkins not starting on CentOS 7 / RHEL 7

Jenkins not starting on CentOS 7 / RHEL 7
Today i was installing Jenkins on a CentOS7 systems. After installing it via Jenkins yum repository, the service was not stating. The java was already installed on the server. Issue You have installed jenkins on a CentOS7 / RHEL7 system. jenkins is not starting via systemctl start jenkins command, and it is throwing journalctl -xn error. Caused ...

OpenVPN with CSF firewall rules

02. February 2017 CentOS, RHEL, SysAdmin 0
OpenVPN with CSF firewall rules
We are a big fan of OpenVPN when it comes to security. Many organizations have already switched to OpenVPN from PPTP etc. NixVPN is my favorite VPN software to host it on a standalone instance. But what if, if you already have a server protected with CSF firewall, and you want to install OpenVPN by ...

Disable SU access for sudo users

11. January 2017 AWS, CentOS, RHEL 0
Disable SU access for sudo users
Some times you need to disable sudo su – access on your environment so that the users will use sudo command always and they will not switch to any other users account unnecessarily Lets see how to do it Edit the /etc/suoders by running visudo visudo Add the below Command Alias Cmnd_Alias BLOCKSU = /bin/su ...

How to log all sudo commands

11. January 2017 RHEL 0
How to log all sudo commands
Some times it’s necessary to log all the sudo commands run in your environment. Let’ss see how to achieve this. Edit the sudoers file by running visudo visudo Add the below line to the Defaults section [sociallocker] Defaults logfile=/var/log/sudo [/sociallocker] Now all the commands from a sudo user will be logged in /var/log/sudo file. [[email protected] ~]# cat /var/log/sudo ...

Last_SQL_Error: Error Table is marked as crashed and should be repaired

30. September 2016 MySQL, SysAdmin 0
Last_SQL_Error: Error Table is marked as crashed and should be repaired
Today we had an issue with our Master-Master replication. Master2 was throwing the below error and the replication was stopped Last_SQL_Errno: 145 Last_SQL_Error: Error 'Table './exampledb/exampletable' is marked as crashed and should be repaired' on query. Default database: 'livewbmy_db'. Query: 'INSERT INTO `exampletable` (`challenge`, `response`, `hashkey`, `expiration`) VALUES ('XBUL', 'xbul', 'a9e0f4e3dxxxxxccccccc0c8f8f1', '2016-09-29 21:10:03')' Since its ...