> If, as you indicate, backups were working fine for a while,
> then I would guess a change has been made to your network
> configuration on client or server.  Perhaps the indicated
> ports (33829 ...) are not allowed.

This is my experience as well.  It turns out that sendbackup
listens to two or three unprivaleged tcp ports for connections
from the backup server.  Have you installed a firewall
lately (iptables)?  If so, you'll have to open incoming TCP
connections to the server IP address for that port range.

Current Debian stable, testing, and unstable all pass
--with-tcpportrange=50000,50100.  Add this type of rule to
your firewall:

iptables -A INPUT -i eth0 -j ACCEPT -p tpc -s AMANDASVR \
    --dport 50000:50100