TIBCO LogLogic LMI - How to find out the UUID from partition devices

TIBCO LogLogic LMI - How to find out the UUID from partition devices

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Article ID: KB0072572

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Updated On:

Products Versions
TIBCO LogLogic Enterprise Virtual Appliance All versions

Description

We have seen a few times that - for some reason the /etc/fstab get partially or fully corrupted. To rebuild that file we need - among other information - the UUIDs from all the partitions. Below is a sample of a healthy /etc/fstab:
  
$ cat /etc/fstab
# Begin /etc/fstab
# filesystem   mount-point  fs-type   options          dump fsck-order
#--------------------------------------------------------------------
UUID=3523a3a7-3075-488a-8d29-3f9cf61d64c5       /            ext4      defaults           1    1
UUID=ec05b6b2-8c4e-4ca2-b8ef-5f811ae511eb       /failsafe    ext4      defaults,nodev           1    2
UUID=8cac16bd-0304-4a6a-a937-db3c7ee65dea        /var         ext4      defaults,nosuid,nodev           1    2
UUID=73bdd5f7-fe3f-4b3a-9f4a-4046bdd5dc26       /loglogic    ext4       defaults,noatime,nodiratime,nodev       1    2
UUID=9e3cfb51-f412-4d82-b21e-47ec704db3f3       /loglogic/data    ext4       defaults,noatime,nodiratime,nodev       1    2
UUID=2fc8fe1d-0f4f-477e-b2d7-0fc5bf8231e3       swap         swap      defaults           0    0
none            /dev/pts     devpts    rw,gid=4,mode=0620 0    0
/var/tmp        /tmp     none    defaults,bind 0    0
shmfs /dev/shm tmpfs defaults,noexec,nosuid,nodev 0 0
 

 

Issue/Introduction

This Article explains how to recover the partitions UUID

Resolution

To recover from a /etc/fstab corruption, we can restore the file from a working appliance running on same OS version. However - the partition's UUID will differ making the system to fail mounting them. 
To grab the correct UUID and other information about the partitions we can leverage command 'blkid' as shown below:
  
# blkid -o full
/dev/sda3: UUID="5ggGBi-UWgq-MKId-oUNn-MFXf-queQ-YFfeA1" TYPE="LVM2_member"
/dev/sda1: LABEL="Root-LLG" UUID="3523a3a7-3075-488a-8d29-3f9cf61d64c5" TYPE="ext4"
/dev/sda2: LABEL="FailFS-LLG" UUID="ec05b6b2-8c4e-4ca2-b8ef-5f811ae511eb" TYPE="ext4"
/dev/mapper/llvg-lllv_var: LABEL="VARFS-LLG" UUID="8cac16bd-0304-4a6a-a937-db3c7ee65dea" TYPE="ext4"
/dev/mapper/llvg-lllv_swap: UUID="2fc8fe1d-0f4f-477e-b2d7-0fc5bf8231e3" TYPE="swap"
/dev/mapper/llvg-lllv_loglogic: LABEL="Loglogic" UUID="73bdd5f7-fe3f-4b3a-9f4a-4046bdd5dc26" TYPE="ext4"
/dev/mapper/llvg-lllv_db: LABEL="Loglogic-data" UUID="9e3cfb51-f412-4d82-b21e-47ec704db3f3" TYPE="ext4"

We can get all information about one specific device by specifying the same in the command:
  
# blkid -p /dev/mapper/llvg-lllv_db
/dev/mapper/llvg-lllv_db: LABEL="Loglogic-data" UUID="9e3cfb51-f412-4d82-b21e-47ec704db3f3" VERSION="1.0" TYPE="ext4" USAGE="filesystem"
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