container image specification

michabbs

Well-Known Member
May 5, 2020
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Is there any technical specification of images file created by vzdump?
It looks like normal tar file with full filesystem dump plus 2 extra files: pct.conf and pct.fw. Did I miss something?
Purpose of pct.conf is obvious. What actually is pct.fw? (It's always zero-length here...)
 
By "container image" I meant lxc, not qemu. :-)

Where does content of pct.fw come from? Is there way to generate it? (For example - pct.conf might be easy generated by "pct config", and of course it is also available in /etc/pve/lxc...)
 
If you add specific firewall rules to a container or VM you will see a /etc/pve/firewall/<vmid>.fw file.
Ach, thanks, I never used it... :)

BTW: I made small test: (1) added fw rule, (2) created snapshot of vm, (3) changed the fw rule, (4) restored the snapshot.
Surprisingly the fw rule was not restored to the "(1)" state. Is this a bug or feature? :-)
 
I made small test: (1) added fw rule, (2) created snapshot of vm, (3) changed the fw rule, (4) restored the snapshot.

firewall rules are restored from backups. snapshots do not contain this information
 
thats where the spec for the vma format is ;)
Well, I was just corrected, containers are backed up differently than VMs... my bad, sorry