AllTechWiki



A Place for All Technical Stuff Linux Cloud etc

LINUX BASIC TROUBLESHOOTING

 Issue 1) Server FS went to readonly mode.


Sol 1) Server rebooted recently but fsck was not heppened due to FS (/etc/fstab 0 0) on perticulat FS.

We tried to umount the FS forcefully but noticed “device busy” error then ran below commands

i) lsof /opt/commvault – Nothing is using
ii) fuser –u /opt/commvaul – None of the process using
iii) fuser –vm /opt/commvault – Noticed one of the user under directory. Hence asked them to come-out of it, Then ran the “fsck” and it’s fixed the issue.

Note: If we are rebooting the server to fix the “read-only” issue, make sure that file system should set to run “fsck” on it( means  should be 1 2, not 0 0 ).

Issue 2) NFS mount issue

Sol 2) If df -h hung in production server before lazy mount try this one, it works 
1)lsof /Backup
2)fuser -ck /Backup
3)umount -f /Backup
4)fuser -ck /Backup
5)umount -f /Backup
gw-server:~ # # umount -f /oracle/NFS_BAK
umount.nfs: /oracle/NFS_BAK: device is busy
gw-server:~ # # fuser -ck /oracle/NFS_BAK
gw-server:~ # # umount -f /oracle/NFS_BAK

Issue 3) Information about Linux SCSI Devices (sdX)
lsscsi -s
ls -d /sys/block/sd*/device/scsi_device/*
ls -d /sys/block/sd*/device/scsi_device/* |awk -F '[/]' '{print $4,"- SCSI",$7}'
ls -l /dev/disk/by-id
http://www.virten.net/2015/08/match-linux-scsi-devices-sdx-to-virtual-disks-in-vmware/

Post a Comment

Previous Post Next Post

Basic Useful Links