vzdump snapshot mode not working

niceboy

Hi,

I'm trying to use vzdump to backup a container and it is failing..

[root@ccg1 ~]# vzdump --compress --dumpdir /home/backup --snapshot 101 INFO: starting new backup job: vzdump --compress --dumpdir /home/backup --snapshot 101 INFO: Starting Backup of VM 101 (openvz) INFO: CTID 101 exist mounted running INFO: status = CTID 101 exist mounted running **INFO: mode failure - unable to detect lvm volume group** **INFO: trying 'suspend' mode instead** INFO: backup mode: suspend INFO: bandwidth limit: 10240 KB/s : :

I can't use solusvm or something similar because I just want to backup my own 5-6 vps only and not going to sell vps hosting.

Any one please help me fix this..

thanks.

ndelaespada

Try this:
vzdump --dumpdir=/home/backup --suspend --compress 101

sman

Is your /vz directory on an LVM partition? Try without the --snapshot.

If you are using LVM check these things:

You need to have at least 512MB free in your LVM volume group, to be able to create snapshots

The directory where you are writing your backup dumps to (usually /vz/dump) should be on a different volume group than the one you are taking a backup from (usually /vz/private)

There is a bug in VZDump.pm that can make the snapshot creation fail

Fixing VZDump.pm

When trying to backup a virtual machine, creation of the snapshot can fail. This is because of a bug in VZDump.pm. In CentOS (and other RHEL derivatives), this file is located in

/usr/share/perl5/PVE/VZDump.pm

On line 622, you will find the following:

if ($line =~ m|^\s*(\S+):(\S+):(\d+(\.\d+))M$|) {

Replace this with:

if ($line =~ m|^\s*(\S+):(\S+):(\d+([\.,]\d+))[mM]$|) {

Save and close the file.

Snapshots will now work with vzdump

http://openvz.org/Backup_of_a_running_container_with_vzdump

niceboy

@ndelaespada vzdump works in stop/suspend mode, but that causes considerable downtime as the container will be around 20-30gb in size. Hence, I would like to use it in snapshot mode which does not cause any downtime.

@sman I already tried fixing vzdump.pm as given in your second method, but it does not work. As I just mentioned, without --snapshot, it does work. But, I need snapshot for taking a backup without any downtime.

Is your /vz directory on an LVM partition?

Btw, I don't know much about lvm partitions. I can see /vz folder in / but don't know if it is on lvm. If I need to put /vz on an lvm partition, how to do it? And, I have enough disk space available for backups.. Here is df -h..

[root@ccg1 ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/vda1              30G  3.1G   25G  11% /
tmpfs                 491M     0  491M   0% /dev/shm

Please help.

prometeus

which version of vzdump are using? The version available as rpm package has this problem with lvm. Just download the version available in a more recent tarball...

niceboy

@prometeus I dont know how to see vzdump version. I checked the manual page but there is no version option. I used the tutor at http://www.zedt.eu/tech/linux/install-vzdump-using-yum-on-centos/ to install vzdump.

prometeus

Download this
http://download2.proxmox.com/sources/vzdump_2011-09-13.tar.gz

you need also cpio and perl-LockFile-Simple (usually into the epel repository)

niceboy

@prometeus I have downloaded http://download2.proxmox.com/sources/vzdump_2011-09-13.tar.gz

perl-LockFile-Simple seems to be already on the system. Is there any tutor on how to use this?

thanks.

prometeus

remove the rpm package then

tar xzf vzdump_2011-09-13.tar.gz 
cd vzdump_2011-09-13
make install

then create a config /etc/vzdump.conf

size:19480
mode:snapshot

where size is the size of the snapshot partition (you need this space to be available in your volume group).

niceboy

sorry for incorrect formatting..

rds100

Did you by any chance press control-c before it finished?

niceboy

Here it is..

[root@ccg1 vzdump_2011-09-13]# make install
rm -f vzdump.1.gz
pod2man -n vzdump -s 1 -r 1.2 -c "Proxmox Documentation"  <vzdump |gzip -c9 >vzdump.1.gz
rm -f vzrestore.1.gz
pod2man -n vzrestore -s 1 -r 1.2 -c "Proxmox Documentation"  <vzrestore |gzip -c9 >vzrestore.1.gz
sed -e s/@@ARCH@@/all/ -e s/@@VERSION@@/1.2/ -e s/@@PKGRELEASE@@/15/ <control.in >control
install -d /usr/sbin
install -m 0755 vzdump /usr/sbin
install -m 0755 vzrestore /usr/sbin
install -d /usr/share/man/man1/
install -m 0644 vzdump.1.gz /usr/share/man/man1/
install -m 0644 vzrestore.1.gz /usr/share/man/man1/
install -d /usr/share/perl5/PVE
install -m 0644 VZDump.pm /usr/share/perl5/PVE
install -d /usr/share/perl5/PVE/VZDump
install -m 0644 Plugin.pm /usr/share/perl5/PVE/VZDump
install -m 0644 OpenVZ.pm /usr/share/perl5/PVE/VZDump

I tried vzdump..

[root@ccg1 vzdump_2011-09-13]# vzdump  --compress --dumpdir /home/backup --snapshot 101
INFO: starting new backup job: vzdump --compress --dumpdir /home/backup --snapshot 101
INFO: Starting Backup of VM 101 (openvz)
INFO: CTID 101 exist mounted running
INFO: status = CTID 101 exist mounted running
INFO: mode failure - unable to detect lvm volume group
INFO: trying 'suspend' mode instead
INFO: backup mode: suspend
INFO: ionice priority: 7
INFO: starting first sync /vz/private/101/ to /home/backup/vzdump-openvz-101-2013_10_18-01_47_49.tmp
^CERROR: Backup of VM 101 failed - interrupted by signal
ERROR: Backup job failed - interrupted by signal

Same result..

niceboy

@rds100 Yes.. I did press Ctrl+C as the backup is using suspend mode again..

prometeus

look like you're using the old perl module or there is some issue with your lvm setup....

niceboy

It seems it is not possible to use snapshot vzdump backups inside a kvm vps.

Any one did tried this earlier and succeeded?

ndelaespada

do you have lvm?

niceboy

I only have the default configuration as given my kvm vps provider.

I did try to display lvms, but it says "No lvm groups found". Therefore, I thought Its not possible to have snapshot backup inside kvm vps. Am I wrong?

niceboy

@zen Is it possible to create lvm inside my kvm vps? If yes, how?

I did go thru numerous googled articles on the subject and could not find any thing useful.

niceboy

@zen could you please share one tutor for this? thx

niceboy

@zen The problem is, most of the articles suggest to use lvm before installing the os and then resize according to the need.

Since I get my kvm vps pre installed with os, Is there any way to do what they are suggesting?

sman

You can run vzdump --suspend. Only downtime is after the first rsync pass where it shuts down the container briefly and does a second rsync pass to catch changes that occurred during the first pass. I've used it quite a bit. Never had any problems.

ndelaespada

It's only a matter of seconds when using suspend, of course, the bigger the VPS is (in size) the longer it takes but in my experience a 25gb vps can take about 60-75 secs suspended while a 1-2GB vps only takes about 2 seconds suspended.

niceboy

If it is just a matter of seconds, I'll use the suspend mode.

Thanks everyone for all the help.

postcd

@sman said:
You can run vzdump --suspend. Only downtime is after the first rsync pass where it shuts down the container briefly and does a second rsync pass to catch changes that occurred during the first pass. I've used it quite a bit. Never had any problems.

on my 80GB large VM, this suspension/downtime and second rsync took almost 13 minutes, how can i have LVM? i have two hdds in softare raid:

Filesystem Size Used Avail Use% Mounted on

/dev/md2 2.0T 150G 1.8T 8% /

tmpfs 7.7G 0 7.7G 0% /dev/shm

/dev/md1 496M 30M 441M 7% /boot