I'm about to build my "Backup" machine which is almost a 1:1 copy (missing SLOG/L2ARC and bit slower CPU to save some power as lightning speed is less important)
My hardware:
2 freenas boxes built in Supermicro SC846's with expander.
Connection served by a LSI9211-8i in each server.
24x 4TB WD RED in both servers. (48 disk total).
Main server having 128G RAMM (overkill). Xeon E5-1620 v3 (3,5ghz quad) And 2x 120GB Samsung 840EVO L2ARC, 2x Intel DC 3500 100G in mirror as SLOG.
The backup server will have also 24x 4TB WD RED in striped mirrors (12x mirror) same as main server to keep iops up, and keep disk management "easy".
This server has 64G ramm, Xeon silver 4112 (2.6Ghz quad) and NO L2ARC or SLOG. I'm hoping the ZIL on the pool will be enough to keep up given the random IOPS the 12 mirrors will give, in case its not enough the main server will get a nice upgrade to its SLOG preparing for 10gbit networking with an intel NVME PCIE model, and the intel sata ssds will go from main to backup server to server as slog.
It will be the same pool layout; 24x WD RED 4TB in mirrored vdevs, same as the main host. But now i'm wondering.
In "old" versions of freenas ZFS replication would be unstable when there were overlapping snapshots;
Every hour kept for 7 days,
Every day kept for 30 days,
Every week kept for 12 months
If replicating the "hourly" one, ZFS replication would be unstable/fail.
Is this still the case?
Now for my true question;
I'm looking at a 5 minute replication interval for the whole recursive snapshot of the pool -being a new task - (as it shouldn't matter, if i save up for 1 hour of 5 minutes, the amount of data/hour is still the same, but every 5 minutes spreads out the load better? (less change of overloading the network for >10minutes). I'm using the hourly/7days one on the CIFS share for "shadowcopy", and then if it was >7days i can restore it daily from the 30days kept one. The case i lose something >30days before noticing it it wasn't that important to me :)
Secondly, is ZFS replication a sequential write to the destination? so importance of the SLOG is not noticeable compared to not having a dedicated SLOG (SSD).
Off course my whole pool is Sync=allways.
I'm looking forward to your help, the documents wasn't really clear on this matter.
My hardware:
2 freenas boxes built in Supermicro SC846's with expander.
Connection served by a LSI9211-8i in each server.
24x 4TB WD RED in both servers. (48 disk total).
Main server having 128G RAMM (overkill). Xeon E5-1620 v3 (3,5ghz quad) And 2x 120GB Samsung 840EVO L2ARC, 2x Intel DC 3500 100G in mirror as SLOG.
The backup server will have also 24x 4TB WD RED in striped mirrors (12x mirror) same as main server to keep iops up, and keep disk management "easy".
This server has 64G ramm, Xeon silver 4112 (2.6Ghz quad) and NO L2ARC or SLOG. I'm hoping the ZIL on the pool will be enough to keep up given the random IOPS the 12 mirrors will give, in case its not enough the main server will get a nice upgrade to its SLOG preparing for 10gbit networking with an intel NVME PCIE model, and the intel sata ssds will go from main to backup server to server as slog.
It will be the same pool layout; 24x WD RED 4TB in mirrored vdevs, same as the main host. But now i'm wondering.
In "old" versions of freenas ZFS replication would be unstable when there were overlapping snapshots;
Every hour kept for 7 days,
Every day kept for 30 days,
Every week kept for 12 months
If replicating the "hourly" one, ZFS replication would be unstable/fail.
Is this still the case?
Now for my true question;
I'm looking at a 5 minute replication interval for the whole recursive snapshot of the pool -being a new task - (as it shouldn't matter, if i save up for 1 hour of 5 minutes, the amount of data/hour is still the same, but every 5 minutes spreads out the load better? (less change of overloading the network for >10minutes). I'm using the hourly/7days one on the CIFS share for "shadowcopy", and then if it was >7days i can restore it daily from the 30days kept one. The case i lose something >30days before noticing it it wasn't that important to me :)
Secondly, is ZFS replication a sequential write to the destination? so importance of the SLOG is not noticeable compared to not having a dedicated SLOG (SSD).
Off course my whole pool is Sync=allways.
I'm looking forward to your help, the documents wasn't really clear on this matter.