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.
Tips
Add EMC Storage in Solaris under VxVM
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).
Extend Filesystem under VxVM
We have already discussed extending a filesystem in AIX under JFS as well as the basic of softpartion where we could also extend its filesystem size. This time we have a task which is under Veritas Volume Manager (VxVM). We need to extend a partition that is being managed by VxVM.
Import Disk Group (DG) in VxVM
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.
How to use snap command on AIX
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.
Fix Garbled Solaris Console
If ever you encounter a console with output such as below, it can be easily be remedied by fixing the /etc/ttydefs file.
Integrated Lights Out Manager (ILOM) CLI Cheat Sheet
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:
Unix or Linux Crontab Headers
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:
Available Commands for Sun / Oracle ALOM
There are times that we really rely on the manual (man) pages when it comes to getting the right options for a certain command under UNIX boxes. But when it comes to Sun/Oracle Advanced Lights Out Manager (ALOM) we can count on with the help command. Here are the commands that you can have with Sun/Oracle Advanced Lights Out Manager
[How To] Access HP iLO via SSH
There are times that we need to do maintenance on a system and we need to connect to its hardware or system controller. With HP boxes they are called HP Integrated Lights-Out (iLO).

