Thursday, March 26, 2015

great piece of scolding of the darn /etc/security/limits.d
https://bugzilla.redhat.com/show_bug.cgi?id=919793

Tuesday, March 10, 2015

Danger of rebuilding a machine with lots of SAN disks in RHEL

This could be a disastrous situation. Say you were asked to rebuild a box from some decommissed box. and Volia someone didn't ummap the SAN disks during the decom process. Not thinking to check and trusting your colleague. You rebuild it via PXE or an ISO image. then... you discovered the OS picked one of the SAN disks to install the OS. If the disk is part of a live database, doesn't matter if there is I/O fencing set up on the cluster. The data is not protected and the database would be corrupted...
The morale?
boot with blacklisting the HBA drivers, common ones are qla2xxx or lpfc at the boot prompt.
"blacklist=qla2xxx,lpfc"

PXE needs to be fixed....