Rsync task not completing sync

[artis1sysop]

I setup a Rsync task 2 weeks ago to sync between 2 FreeNAS servers across a site-to-site VPN. What is being sync'd is a nightly incremental backup of another server which is running its own backup software and backing up it's increments to the FreeNAS server. We're using Rsync to sync to another FreeNAS server across a site-to-site VPN so that we have an off-site copy of the backup files.

It's been 2 weeks, and the files/folders between the 2 FreeNAS servers are still not in sync.

I can Rsync a smaller test folder of the backup files, and the Rsync between the 2 FreeNAS servers works great.
When I try to Rsync the large folder of the backup files, it does some of the files but it's been 2 weeks and they're still not sync'd
The folder size to Rsync is 2.5 TB
There are only about 20 GB per day of new files added that need to be sync'd
We have a 100 mbps connection at both sites. It will be somewhat less because of the VPN overhead (I don't know how to measure this)

Even with a 100 mbps connection (let's say it's 50 mbps with the VPN overhead), I would think the Rsync of 2.5 TB would be done well within 2 weeks.

How can I get this to work?

 

[dlavigne]

Did you find a solution for this?

 

[artis1sysop]

I think I may have stumbled across a solution (hopefully) yesterday. I'm trying it out today.

We have Synology NAS boxes, FreeNAS boxes, and SonicWALL gateway/firewalls.

The site-2-site VPN rsyncs fail no matter what configuration of boxes I use between sites. Local rsyncs work perfectly fine.
Synology rsync --> VPN --> Synology = fail
Synology rsync --> VPN --> FreeNAS = fail
FreeNAS rsync --> VPN --> FreeNAS = fail

I suspected this had to do with the VPN. I stumbled across a thread on a Synology forum discussing rsync problems over site-to-site VPN using SonicWALLs. The solution was to disable the Intrusion Prevention System (IPS) on the SonicWALLs for the LAN zone. The SonicWALL detects rsync as a low-level threat.

Here's the thread:
http://pointclickanywhere.com/sonicwall-ips-blocking-synology-backup/

Since I didn't want to disable IPS entirely on the LAN zone, I just excluded the IP addresses of the Synology NAS and FreeNAS devices from IPS.

We'll see how this goes...