yboetz
Received snapshot does not contain the expected files
Hi.
I have just started with pyznsap.
I am taking snapshots from a remote XigmaNAS server.
My pyznap.conf is
[ssh:22:[email protected]:pool1/www]
frequent = 4
hourly = 24
daily = 7
weekly = 4
monthly = 6
yearly = 1
snap = yes
clean = yes
dest = poolUSB/NAS
dest_auto_create = yes
compress = lz4
In the NAS, I have the following content and no previous snapshots:
nas4free: ~# ls -la /mnt/pool1/www/
total 10
drwxrwxr-x 2 root wheel 3 Jan 13 20:39 .
drwxrwxrwx 15 www wheel 15 Dec 12 22:08 ..
-rw-r--r-- 1 root wheel 8 Jan 13 20:39 kk.txt
nas4free: ~#
The results of pyznap snap and later pyznap send:
pi@raspberrypi:/mnt $ sudo pyznap -v snap
Jan 13 20:44:51 INFO: Starting pyznap...
Jan 13 20:44:51 INFO: Taking snapshots...
Jan 13 20:44:52 DEBUG: Taking snapshots on [email protected]:pool1/www...
Jan 13 20:44:52 INFO: Taking snapshot [email protected]:pool1/www@pyznap_2021-01-13_20:44:52_yearly...
Jan 13 20:44:53 INFO: Taking snapshot [email protected]:pool1/www@pyznap_2021-01-13_20:44:53_monthly...
Jan 13 20:44:53 INFO: Taking snapshot [email protected]:pool1/www@pyznap_2021-01-13_20:44:53_weekly...
Jan 13 20:44:54 INFO: Taking snapshot [email protected]:pool1/www@pyznap_2021-01-13_20:44:54_daily...
Jan 13 20:44:54 INFO: Taking snapshot [email protected]:pool1/www@pyznap_2021-01-13_20:44:54_hourly...
Jan 13 20:44:55 INFO: Taking snapshot [email protected]:pool1/www@pyznap_2021-01-13_20:44:55_frequent...
Jan 13 20:44:55 INFO: Cleaning snapshots...
Jan 13 20:44:56 DEBUG: Cleaning snapshots on [email protected]:pool1/www...
Jan 13 20:44:56 INFO: Finished successfully...
pi@raspberrypi:/mnt $ sudo pyznap -v send
Jan 13 20:45:06 INFO: Starting pyznap...
Jan 13 20:45:06 INFO: Sending snapshots...
Jan 13 20:45:07 WARNING: lz4 does not exist on [email protected], continuing without compression...
Jan 13 20:45:07 INFO: Destination poolUSB/NAS does not exist, will create it...
Jan 13 20:45:08 INFO: Successfully created poolUSB/NAS...
Jan 13 20:45:08 DEBUG: Sending [email protected]:pool1/www to poolUSB/NAS...
Jan 13 20:45:08 INFO: No common snapshots on poolUSB/NAS, sending oldest snapshot [email protected]:pool1/www@pyznap_2021-01-13_20:44:52_yearly (~37.6K)...
Jan 13 20:45:09 INFO: Updating poolUSB/NAS with recent snapshot [email protected]:pool1/www@pyznap_2021-01-13_20:44:55_frequent (~3.0K)...
Jan 13 20:45:10 INFO: poolUSB/NAS is up to date...
Jan 13 20:45:10 INFO: Finished successfully...
The snapshots at destination are below:
pi@raspberrypi:/mnt $ zfs list -t snapshot
NAME USED AVAIL REFER MOUNTPOINT
poolUSB/NAS@pyznap_2021-01-13_20:44:52_yearly 0B - 88K -
poolUSB/NAS@pyznap_2021-01-13_20:44:53_monthly 0B - 88K -
poolUSB/NAS@pyznap_2021-01-13_20:44:53_weekly 0B - 88K -
poolUSB/NAS@pyznap_2021-01-13_20:44:54_daily 0B - 88K -
poolUSB/NAS@pyznap_2021-01-13_20:44:54_hourly 0B - 88K -
poolUSB/NAS@pyznap_2021-01-13_20:44:55_frequent 0B - 88K -
But, the dataset has no file inside:
pi@raspberrypi:/mnt $ ls -la /mnt/poolUSB/NAS/
total 2
drwxr-xr-x 2 root root 2 ene 13 20:16 .
drwxr-xr-x 4 root root 4 ene 13 20:16 ..
pi@raspberrypi:/mnt $
What is the problem?
BTW, f couse lz4 is available in the NAS server. In fact, the pool1/www dataset has the compression set as lz4. Why does that warning appear?
pool1/www compression lz4 local
Thanks!
For compression the algorithm must be installed as a system package, e.g. through apt install lz4 on Ubuntu. pyznap cannot use the built-in lz4 from zfs.
About the missing file: Make sure the filesystem is mounted. pyznap has a problem where it unmounts filesystems for send/recv, so your dataset might just not be mounted.
Hi.
Thanks for the fast reply.
I have just realized that in embedded XigmaNAS the liblz4 package is not installed, so the lz4 command cannot be invoked. Is there any option to set a no-compression method for the transfer?
Thanks, the destination dataset was unmonted, indeed. Then, I mounted it manually by zfs mount pooUSB/NAS and I can see my test files :) This behaviour is a bug or it is deliberate, since, for this case, it was newly created by the pyznap send? Once mounted, I redid some pyzsnap send and it continue being mounted.
Thanks!
If you don't want any compression you can set compress = none. Default is lzop, which helps quite a bit over ssh when your data is compressible, like lots of text documents. If you only have pictures/media, then compression doesn't make sense and just disable it as mentioned.
It's a mix of bug and deliberate :). For the zfs send/recv I have to set a flag in the receive command that unmounts filesystems. Sometimes they are then remounted, but often times not. So the flag is deliberate, but the datasets being mounted/unmounted after the send is a bit buggy, and I haven't figured out how to fix this. For me the datasets also stay mounted after I manually remount them once, but other people have said for them it's different.