This topic has been marked solved and closed to new posts due to inactivity. We hope you'll join the conversation by posting to an open topic or starting a new one.
Although RAIDiatior is telling me that 3TB on each disk has been assigned my total Volume Capacity is still 9250GB, where I expected that it should have been increased by approx. 2TB.
Anyone who could help me sorting out why this volume is not expanding?
# lvdisplay
--- Logical volume ---
LV Name /dev/c/c
VG Name c
LV UUID 58i8fT-VZhX-ntye-IWZX-mxhr-uDci-snOtLM
LV Write Access read/write
LV Status available
# open 1
LV Size 9.07 TB
Current LE 148592
Segments 2
Allocation inherit
Read ahead sectors 0
Block device 253:0
# pvdisplay
--- Physical volume ---
PV Name /dev/md2
VG Name c
PV Size 7.26 TB / not usable 0
Allocatable yes (but full)
PE Size (KByte) 65536
Total PE 118944
Free PE 0
Allocated PE 118944
PV UUID E3ORym-0inG-l1CX-gueV-NZIV-mGUI-vR4JG4
--- Physical volume ---
PV Name /dev/md3
VG Name c
PV Size 1.82 TB / not usable 0
Allocatable yes
PE Size (KByte) 65536
Total PE 29808
Free PE 160
Allocated PE 29648
PV UUID eiX7nG-hwof-NbMi-ulKJ-mSLx-71HI-2MH6zK
After unmounting volume c I've resized the physical volume /dev/md3 (since the RAID6 array has already been expended) and extendend the logical volume with 1.82T. After that I've resized the ext4 filesystem on /dev/c/c:
Also, there is an 8 TiB growth limit from the factory install (or the more recent factory default). Is it possible that you have reached that limit? Is there anything in the logs that suggests that expansion has failed?
I've started with a capacity of 7.5TB, so the 8 TiB growth limit should not be a problem. The logs are not stating anything usefull, besides that it is trying to extend the logical volume by "0" bytes:
[2015/09/26 15:03:15 3419] LINE 4374: exec command: lvextend /dev/c/c -l +0
New size (148592 extents) matches existing size (148592 extents)
Since mdadm was showing that the partitions sda4 and sdc4 are not part of md3 (RAID 6), I'm now trying to add them manually:
After unmounting volume c I've resized the physical volume /dev/md3 (since the RAID6 array has already been expended) and extendend the logical volume with 1.82T. After that I've resized the ext4 filesystem on /dev/c/c:
Is far as I know from answers around the internet, RAID 6 bij default needs at least 4 drives (of the same size, that is) to operate (which is strange as technically for dual reduncandy 3 should be enough). I guess if you added a 4th 4TB drive, it would have expanded as expected.
It's good to know one can manually override this behaviour.
The volume capacity now is the same as it would have been with 6x3TB disks. If another 4TB disk is added then offline volume expansion may be possible to expand it a further couple of TB.
