HI guys
Sorry for not uploading this to bugzilla - I couldnt get the password code email delivered to my registered address to update the login - so sharing here as “no route to host” 
!
Running IPFire core update 203 (now) after updating from 202 earlier
on an HP DL360 - dual proc 16gb RAM
initially the 202-203 upgrade seemed to work well, but into the evening I had complaints that services behind my firewall couldn’t be reached and that outbound traffic was not being delivered.
at first It looked like I was caught in the DNS change debarcle as my DNS servers were all showing as down , but after a while I realised that I couldn’t hit servers even using their IP address - something was very wrong!
I have one upstream router between red0 and the optical network terminator (as a guest network) so I expected to see a default route pointing to it
netstat -rn
no route for 0.0.0.0 !!!
After my initial “WT*?” moment I input
ip route add default via {UPSTREAM_ROUTER_IP} dev red0
straight away all connectivity was restored
As a test I bounced red0 with
/etc/rc.d/init.d/network stop red
/etc/rc.d/init.d/network start red
starting red took a LONG time but the default route was successfully re-added automatically this time
Its past midnight here now, and the firewall is in the roof, so I will not do a full on reboot test until the morning as if manual intervention is needed my size 48s will wake the whole house!
Hope this helps someone else out there - it may not be your DNS ! it wasn’t mine !
regards
BB