Category: CentOS
A Poor Man’s VPN: Proxy Web Connection to Remote Server (via SSH and Tunnel)
Did you ever have a situation where you needed to access a website that had an IP restriction in place? I recently had a situation where I needed to access the web via my university connection (due to IP restrictions placed on accessing databases of research papers). They do not have a VPN setup so [...]
Command Line Packet Sniff Existing Running Process in Linux
Have you ever come across a server that is doing a lot of traffic? Maybe you have logged in to see a process running at 100% CPU, so you know the culprit, but instead of kill -9ing it, wouldn’t it be great to see what exactly it is up to? Or even if you see [...]
Easy Search and Replace in Multiple Files on Linux Command Line
I recently came across a typo that existed in a bunch of html files on my web server. I thought it should be easy enough to change, but since it was in a number of files, editing it by hand would be time consuming. Fortunately, there is an easy, one liner command to replace the [...]
Installing And Compiling Zabbix Client / Agent
Zabbix is an excellent system monitoring package. It does everything from basic availability checking to detailed system resource analysis. It is capable of graphing the variables pulled from the system, and alerting admins if there is a problem or something needed for attention. Once you have the Zabbix server set up, you need to install [...]
Memory Allocation Problems on Xen Server & Fix
Recently I started seeing this error while provisioning Xen VPSes on a server with 8GB of RAM: 12[2009-03-23 15:51:40 xend.XendDomainInfo 3310] DEBUG (XendDomainInfo:1603) XendDomainInfo.destroy: domid=None [2009-03-23 15:51:40 xend 3310] ERROR (xmlrpclib2:184) (12, ‘Cannot allocate memory’) I checked the memory, and sure enough, all of the VPSes were using up the memory. More specifically, dom0 (the [...]
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