There are a bunch of runlevel for UNIX or Linux which is also called init level or mode of operation. Usually there are seven init or runlevels (0 to 6). Only one runlevel can be running at a single time.
As UNIX system administrators – we need our Operating Systems running in optimal state every time. The same is what we want to our storage systems. In EMC Powerpath there are a couple of failover policies that we can enforce to our storage devices but we must always use the one that is best suitable. We have here a LUN that is currently under Basic Failover policy even though the storage is CLARiiON:
Have you ever encounter rebooting a server and your Veritas filesystems are missing? Most cases these filesystems were not imported during boot up and is not available for OS to use. Importing a disk groups in VxVM does not need any reboot, follow these simple steps and you will be able to get back your disk groups in no time.
For any software or hardware issues with AIX, logging a case with IBM – the support team will always ask for snap files. Snap files will collect all system configuration that will help and guide the IBM support team to track whatever issue there is on the system.
Even though cron is our usual lifesaver for redundant tasks on a Unix or Linux Systems, there are times that we really forget the syntax that is needed for our cronjobs. Here is a simple yet effective headers that we could place on top of the crontab as comments:
It is a very sad news for all of us. A true pioneer in modern computing and the one that revolutionizes on what we are all using today. Without C language, we will not have Java, C++, Basic. Without Unix, what Operating System will the world would be using.
Managing printer is one of the least task of a Unix System Admin. But printer management is typically easy to get along with as there is just minimal commands and options that we use. Here are some of my trusted commands to manage printers:
Today we encountered a degraded policy in EMC PowerPath disk on one of our SUN/Oracle Solaris boxes. We found out that the license for our PowerPath was not properly installed on the system. With this current issue – our disks is only running on Basic Failover policy which is not recommended for CLARiiON disks. To mitigate the issue, we need to install the license and set the policy back to CLARiiON Optimization Policy.
When your work is related to computer either your a developer, sysadmin, hacker, artist, consultant, or programmer – let’s admit it, we all have our own little spare time. Here is an illustration that I saw while wandering around the web.