[Users] Problems encountered increasing CT diskspace with layout=ploop

[Kir Kolyshkin]

On 03/23/2012 10:27 PM, jjs - mainphrame wrote:
> We can successfully resize the simfs-based CT 777:
>
> [root at mrmber conf]#  vzctl set 777 --diskspace=20000000:24000000 --save
> CT configuration saved to /etc/vz/conf/777.conf

For simfs case, this is not a real resize, but change of vzquota values. 
That is why you have two values for quota -- soft and hard (and 
--quotatime to set a grace period).
>
> But attempting to resize ploop-based CT 779 results in an error:
>
> [root at mrmber conf]# vzctl set 779 --diskspace=20000000:24000000 --save

This is irrelevant to the bug report, but just in case:
1 there's no need to specify two values for ploop disk size
2 you can use suffixes (like --diskspace 24G).

> Can't ioctl mount_point: No such file or directory
> Failed to resize image: Can't ioctl mount_point: No such file or 
> directory [3]

This means ploop can't find the balloon file. That's pretty strange.

1 Have you created this CT using the same version of vzctl and ploop?
2 Do you have anything strange in dmesg?
3 Are you able to stop/start/mount/umount this CT?

In the meantime, I have tried to do the same as you did on my box 
(running the same version of kernel, vzctl, and ploop):

[root at dhcp-10-30-21-127 ~]# vzctl set 200 --diskspace=20000000:24000000 
--save
Growing dev=/dev/ploop0 size=4613734 sectors (new size=48000000)
Storing GPT
Executing: /sbin/resize2fs -p /dev/ploop0p1
resize2fs 1.41.12 (17-May-2010)
Filesystem at /dev/ploop0p1 is mounted on /vz/root/200; on-line resizing 
required
old desc_blocks = 1, new_desc_blocks = 2
Performing an on-line resize of /dev/ploop0p1 to 5999739 (4k) blocks.
The filesystem on /dev/ploop0p1 is now 5999739 blocks long.

Executing: /sbin/tune2fs -r 300000 /dev/ploop0p1
tune2fs 1.41.12 (17-May-2010)
Setting reserved blocks count to 300000
CT configuration saved to /etc/vz/conf/200.conf
[root at dhcp-10-30-21-127 ~]# vzctl exec 200 df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/ploop0p1          23G  674M   21G   4% /


> CT configuration saved to /etc/vz/conf/779.conf
>
> [root at mrmber conf]# for i in `vzlist -1`; do echo $i; vzctl exec $i df 
> -T ; done
> 777
> Filesystem    Type   1K-blocks      Used Available Use% Mounted on
> /dev/simfs   simfs    20000000    376820  18532204   2% /
> tmpfs        tmpfs      131072         0    131072   0% /lib/init/rw
> tmpfs        tmpfs      131072         0    131072   0% /dev/shm
> 779
> Filesystem    Type   1K-blocks      Used Available Use% Mounted on
> /dev/ploop0p1 ext4     2268760    445756   1707756  21% /
> tmpfs        tmpfs      131072         0    131072   0% /lib/init/rw
> tmpfs        tmpfs      131072         0    131072   0% /dev/shm
> [root at mrmber conf]#
>
> Any advice on where to look for more info? dmesg had nothing to say 
> about it, and vzctl.log says only what the command reported above.
>
> Regards,
>
> Joe
>