LVM tricks – determine the age of the system
After some researching and reading some ITRC, I found a way to get the age of the system. This is done with reading and decrypting the LVM header from the system disks. At first, we need to find out...
View ArticleChecking if a disk is failing
I know several ways to identify bad disks, e.g. there is the EMS tool and you can also see some SCSI error messages in syslog. But here is a low-level way to check if a disk is failing: # echo...
View ArticleFind out the disk we were booted from
Here is a quick way to read directly from the running kernel from which disk the system was started: # echo "boot_string/S" | adb /stand/vmunix /dev/kmem boot_string: boot_string:...
View ArticleSome thoughts about mediainit – low level formatting and why it mustn’t be done
mediainit is neither required nor recommended for most modern disks. In fact, mediainit might damage some (semi-)modern disks. Even the most basic SCSI disks today have a built-in defect management...
View ArticleVariable sizes in KSH
It looks like the POSIX shell doesn’t support variable sizes greater than 2 Gigabytes. In the following example, the LIMIT variable is of 1 Gbyte, and the VALUE is 4 GBytes. # LIMIT=1073741824 #...
View ArticleCrash dump analysis with crashinfo
If the system becomes uncontrollable, the last resort is to push the TOC button or run the TC command from the GSP. This will cause the system to generate a crash dump under /var/adm/crash. By...
View ArticleAdd a custom screensaver to CDE
The Common Desktop Environment (CDE) has many screensavers for use, you can select which you like the most from the Style Manager Screen menu. There is the screen saver action definition, which...
View ArticlePhysical vs. Logical I/O
If you do performance tuning or troubleshooting with glance probably you have observed the terms logical I/O and physical I/O. This post is to clarify these shortly: Physical I/O: the traffic toward...
View Article
