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IBM AIX : Extending Mirroring Synchronizing ROOTVG

 Usually we get an old_rootvg or altinst_rootvg volume group  after alt_disk backup, upgrade or migration. On this tutorial we will  detail the steps of removing altinst_rootvg , then extending rootvg  and Mirror rootvg with background synchronization.

Let’s  See

Step 1: List the PV with command lspv as below to see which PV hold the old_rootvg / altinst_rootvg  VG . On this example, you can see the altinst_rootvg on hdisk6
removing altinst_rootvg
Step 2:Now let remove  altinst_rootvg using alt_disk_install command with -X flag as below.
After removing altinst_rootvg
Step 3 : After removing altinst_rootvg  list again the PVs again now the hdisk6 become None.
Cleaning up AIX ALTINST
Step 4: Extending rootvg to include hdisk6 using extendvg( -f for force ) command as below and list PVs to verify  now it is part of rootvg. Now we can see hdisk6 is assigned to rootvg.
Cleaning up AIX ALTINST
Cleaning up AIX ALTINST
Step 5 : Now Mirror and Synchronized the rootvg VG using mirrorvg command with -S flag , which will run synchronization in background.
a) Before Mirroring LPs and PPs number is same means it is not mirrored yet.
Cleaning up AIX ALTINST
b) Mirroring using “mirrorvg –S rootvg .
Cleaning up AIX ALTINST
From the man page of mirrorvg
-S Background Sync Returns the mirrorvg command immediately and starts a background syncvg of the volume group. With this option, it is not obvious when the mirrors have completely finished their synchronization. owever, as portions of the mirrors become synchronized, they are immediately used by the operating system in mirror usage.
c) After Mirroring: It might take several minutes to sync LVs as you can see in the below lots of LVs are still in stale state
Cleaning up AIX ALTINST
d) After Full Sync The Out Put will be like below
Cleaning up AIX ALTINST
Step 6 : Re Create the boot image on both rootvg’s PV hdisk6 and hdisk7 and include in boot list.
bootlist -o -m normal
# output: hdisk7 blv=hd5

bosboot -ad hdisk7
# output: bosboot: Boot image is 22698 512 byte blocks.
bosboot -ad hdisk6
# output: bosboot: Boot image is 22698 512 byte blocks

bootlist -o -m normal   hdisk7 blv=hd5  hdisk6 blv=hd5
# output: hdisk7 blv=hd5
# output: hdisk6 blv=hd5

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