Poor network backup performance

Hi all,

I've been using Bacula to back up my NAS for some time, and it's been 
working well. I see effective backup rates of about 30MB/s all told 
(100MB+ unspooling from SSD to tape, maxing out the LTO6 drive).

Unfortunately when I added my desktop PC to the backup cycle, I found 
that the effective rate dropped like a rock, to single-digit megabytes 
per seconds.

The machines are both fairly fast -- the desktop machine (backup source 
running the FD) is a Ryzen 5 5600X, and the server (with the SAS SSD and 
tape drive) is an Intel Core i5-9400.
The network is gigabit end-to-end, and the transfer rates I'm seeing are 
very poor. Other applications taking the same path are much faster.

Both systems are running Debian derivatives -- the desktop runs Mint 
with Bacula 13.0.4, and the server runs Ubuntu 24.04 with the same 
version of Bacula.

Is there anything I can do to improve performance backing up over the 
network, before I resort to a nightly Rsync from the workstation to the 
server and backing up from there?

Thanks.
-- 
Phil.
[email protected]
https://www.philpem.me.uk/