Maximum number of ZFS snapshots?

K

Klinki

Hello,

i am using sysutils/freebsd-snapshot for regular snapshot of my ZFS filesystem. It works so far very nicely but there is one warning in the logs which i do not understand:
Code: 
snapshot: schedule /,/usr,/var:12:30:24 on filesystem / would require more than maximum number of 20 possible snapshots

I checked the periodic snapshot script and the 20 is a hard coded value. But as far as i know is there no such small limit of snapshots. Can anyone help me out to eliminate this warning.

Thanks in advance.
 
zfs is not limited to snapshot counf (On my server I make 1 snapshot per hour and keep them for 5 days, then I have 2 snapshots per day, that I keep 2 weeks, and 1 snapshot per month, that I keep a year...... Works fine)

But UFS indeed is limited to 20 snapshots....
I think you're using UFS and not ZFS (at least for some filesystems)

i'm using sysutils/zfsnap (my own baby)
 
killasmurf86 said:
zfs is not limited to snapshot counf

But UFS indeed is limited to 20 snapshots....
I think you're using UFS and not ZFS (at least for some filesystems)
Click to expand...

Thanks for clarification. This is indeed the problem. After hinting me in this direction i found the relevant sentence in the man page:
Code: 
Keep in mind that a maximum total
number of 20 snapshots can be created on a UFS filesystem only.

Guess i have to check another snapshot program :D
 
If you get a chance read the whitepapers on ZFS (from Sun now Oracle) they are very interesting - Here is some lit from Wikipedia

* 2^64 — Number of snapshots of any file system[14]

ZFS was made in every regard to be so large it would never be possible to reach it's limitations.
 
shitson said:
If you get a chance read the whitepapers on ZFS (from Sun now Oracle) they are very interesting - Here is some lit from Wikipedia

* 2^64 — Number of snapshots of any file system[14]

ZFS was made in every regard to be so large it would never be possible to reach it's limitations.
Click to expand...

Like I said... it's Unlimited about of snapshots... (ok it's limited, but by the time you reach that limit, there will be yfs (yottabyte file system) with yotabyte HDD's on phones. lol)

btw 2^64=18'446'744'073'709'551'616
 
ZFS snapshot can be 2^64 but not UFS snapshot on ZFS - there seems to be the 20 snapshot limit.
I am using now killasmuf86s port of sysutils/zfsnap and it's working like a charm.
 
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