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.
New task at hand fellow UNIX Administrators. Now we need to discover the new (EMC) LUNs presented by the Storage team and make it available into Veritas Volume Manager (VxVM) and extend one of the filesystem under Veritas Filesystem (VxFS).
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.
If ever you encounter a console with output such as below, it can be easily be remedied by fixing the /etc/ttydefs file.
Missed the old SunSolve where you can check and download the latest patches and fixes for Sun Solaris? We all know that SunSolve is now decommisioned by Oracle and has replaced it with Oracle Support and thanks to it’s Flash interface its one hell of sluggish support site.
Learning the Integrated Lights Out Manager (ILOM) will be a big help when a System Administrator cannot login anymore to the server. ILOM can be accessed via IP network or serial console. Here are some of the most commonly used commands that could get anyone on track on managing the ILOM:
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: