3

I have the following setup with FreeBSD jails and VNET which is supposed to grow into a DNS core net lab setup. The jailhost and the jails are running FreeBSD 12.1. The jails are connected by epair interfaces. The BRAS jail which is supposed to act as the network's edge router is connected to the jail host by epair interfaces. The jailhost runs a pf based NAT

Network topology

I can reach hosts in the WAN from the BRAS jail without a problem. The problem is that I cannot reach anything behind the BRAS jail from the DNS. Forwarding on the BRAS is enabled and the pf rules for the NAT are broad enough to allow traffic from the DNS's network.

If I understood it correctly I don't need multiple fibs on the jailhost using VNET, please correct me if I'm wrong. That part of jails is not documented too well.

root@bras:/ # netstat -r
Routing tables

Internet:
Destination        Gateway            Flags     Netif Expire
default            172.16.3.1         UGS     epair8b
localhost          link#1             UH          lo0
172.16.1.0/30      link#4             U       epair7a
172.16.1.1         link#4             UHS         lo0
172.16.3.0/30      link#5             U       epair8b
172.16.3.2         link#5             UHS         lo0
root@dns:/ # netstat -r
Routing tables

Internet:
Destination        Gateway            Flags     Netif Expire
default            172.16.1.1         UGS     epair7b
localhost          link#1             UH          lo0
172.16.1.0/30      link#2             U       epair7b
172.16.1.2         link#2             UHS         lo0
# pf.conf jailhost
ext_if="vtnet0"
jail_if="epair8a"

IP_PUB="redacted"
IP_JAIL="172.16.3.1"

NET_JAIL="172.16.0.0/16"

scrub in all

nat pass on $ext_if from $NET_JAIL to any -> $IP_PUB
2

Long story short, it wasn't related to jails or epair at all. I just forgot to set an entry for the return route.

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.