This is a repost from the old forum here
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I have seen this topic several times, and finally somebody has documented the steps* that QNAP support executes
WARNING: Use these at your own risk!
Commands with explanation (as far as I can make them out)
list drb devices, storage volumes will be listed (note down the one with the missing size e.g. drbd1 and vg288)
[~] # pvs
PV VG Fmt Attr PSize PFree
/dev/drbd1 vg288 lvm2 a-- 7.27t 3.60t
Find the correct md device (here it’s md1)
[~] # md_checker
Welcome to MD superblock checker (v2.0) - have a nice day~
Scanning system...
RAID metadata found!
UUID: 2287586a:dd935b28:8f1d0240:2c5627bf
Level: raid6
Devices: 6
Name: md1
Chunk Size: 512K
md Version: 1.0
Creation Time: Oct 9 15:48:10 2019
Status: ONLINE (md1) [UUUUUU]
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Enclosure | Port | Block Dev Name | # | Status | Last Update Time | Events | Array State
===============================================================================================
NAS_HOST 7 /dev/sdf3 0 Active Feb 23 09:44:21 2024 1634759 AAAAAA
NAS_HOST 8 /dev/sdc3 1 Active Feb 23 09:44:21 2024 1634759 AAAAAA
NAS_HOST 3 /dev/sde3 2 Active Feb 23 09:44:21 2024 1634759 AAAAAA
NAS_HOST 6 /dev/sdh3 3 Active Feb 23 09:44:21 2024 1634759 AAAAAA
NAS_HOST 5 /dev/sdg3 4 Active Feb 23 09:44:21 2024 1634759 AAAAAA
NAS_HOST 4 /dev/sdd3 5 Active Feb 23 09:44:21 2024 1634759 AAAAAA
===============================================================================================
grow the physical device (e.g. md1)
mdadm --grow /dev/md1 --size=max
resize the drbd device (drbd1)
drbdadm -- --assume-peer-has-space resize r1
pvresize /dev/drbd1
resize vg device (vg288)
lvresize vg288/lvl -l +100%"FREE" -f
If the size has not changed after a reboot, resize the filesystem as well (see /dev/mapper/ for the correct cachedev)
resize2fs_64 /dev/mapper/cachedev1