Replication - how much date is transfered

[Jaroslav Jasek]

Hi,
I have two FrreNAS boxes - one for the replication.
I set for replication one dataset - this have 530 GB . Firts I start replication in the local LAN and after this I move the FreeNAS box off-line and replication run throught slow WAN. I see in the snapshot the size - 15 - 20 GB. But when start the replication I see, that replication tranfrer through WAN many GB .
Replication run not as incremental ? - not tranfer only new data ? - transfer alll data from the dataset ?

Thanks
Jaro

 

[dlavigne]

The initial replication can take a significant period of time, from many hours to possibly days, as the structure of the entire ZFS pool needs to be recreated on the remote system. The actual time will depend upon the size of the pool and the speed of the network. Subsequent replications will take far less time, as only the modified data will be replicated. If the security policy allows it, temporarily change the “Encryption Cipher” to Disabled until the initial replication is complete. This will turn off encryption but will speed up the replication. The “Encryption Cipher” can then be changed to Standard or Fast for subsequent replications.

Depending upon the FreeNAS version, the encryption option may be "Enable High Speed Ciphers", "Encryption Cipher", or not be an available option at all.

 

[Jaroslav Jasek]

Thanks for the explanation.
As I write, I start initial replication on the local (speed) LAN . This take mamy hours - as You write - this is OK.
But after this initial replication I move the FreeNAS box in another place and I await , that replication transfer through slow WAN only modified data - as you write. Can I somehow see, how many are this modified data ? - this is not the size the snapshot ?
I see the snapshot size arround 16 MB, but replication tranfer lot of GB data.

Thanks
Jaro

 

[Jaroslav Jasek]

Hi,
Can anybody help me found the answer about the huge data transfer by replication ?
Jaro.

 

[dlavigne]

Did you figure this out? If not, are you sure that the intial replication completed successfully?

 

[Jaroslav Jasek]

Hi,
I try update my FreeNAS to 9.2.1.8 - after this run all well. Replication transfer only changed data - very fast !
I dont know, if this was problem on my FreeNAS box with previous version, or any other - but immediately after update run all well :-(
Regards
Jaro