Backing up ZFS Snapshots

[therm]

Hello Guys,

I am using amanda for a while but some Servers sometimes failed to backup with such a message

"host / lev 0 FAILED "/opt/csw/libexec/amanda/runtar exited with status 1: see /tmp/amanda/client/test/sendsize.20100504195719.debug" .

I read something that this might have something to do with changing data on that device e.g. databases.

So I decided to switch to use zfs-snapshots, but it seems to me that amanda does the snapshot but does not use it for backup; instead it dumps the original device:

host /.zfs lev 0 FAILED "/opt/csw/libexec/amanda/runtar exited with status 1: see /tmp/amanda/client/test/sendsize.20100504195719.debug"

Here is my config:

define script-tool script_zfs_snapshot {
comment "zfs-snapshot"
plugin "amzfs-snapshot"
execute-where client
execute-on pre-dle-amcheck, post-dle-amcheck, pre-dle-estimate, post-dle-estimate, pre-dle-backup, post-dle-backup
property "DF-PATH" "/usr/sbin/df"
property "ZFS-PATH" "/usr/sbin/zfs"
}
define dumptype zfs-snapshot {
global
program "GNUTAR"
# application "app_amgtar"
script "script_zfs_snapshot"
auth "bsdtcp"
}

disklist:
host /.zfs / zfs-snapshot

In the logs it seems that amanda dumps / instead of /.zfs.

How do I backup the real snapshot?

Thanks for your answers.
therm

[martineau]

GNUTAR can't backup a zfs snapshot.
You must use the application amgtar.

[therm]

Hi martineau,

and thanks for your answer. I am testing it now with app_amgtar. But were is the reason why it does not work with GNUTAR, is a zfs-snapshot not just a folder wich I have do dump?

[martineau]

Because GNUTAR don't know where the snapshot is, and we don't add new feature in GNUTAR.

[therm]

Ok, but exactly this I thought was giving gnutar from amanda in form of the first entry "/.zfs" :

host /.zfs / zfs-snapshot

Or the other way: I thought that it is easy to implement new sorts of dumps such as dumping linux lvm, by writing a script making a snapshot before and deleting it after backup and dumping it with gnutar because my opinion is that I dump a folder that was generated by my script before the dump... ( Does anyone understand what I mean?)

Best regards
therm

[martineau]

amgtar is an improved GNUTAR, with many new features.

With amgtar, the script send the information where the snapshot is to amgtar.
It can't send that information to GNUTAR and we will not add that feature.
We don't add new feature to GNUTAR
Please use amgtar if you want new feature.