Dual Homed Mail Server

UCS - Univention Corporate Server
#1

We have a UCS Mail Server that is setup with 2 network interfaces one on the internal network and one on the external network. This server acts as our External Email Gateway as well as our WebMail Server for employees.

We are having issues with getting the UCS GUI to show up on both the internal and external interfaces, we want to be able to access webmail from both external and internal networks. Right now it only works on the internal network.

We are able to ping the external interface as well as internal interfaces. Port scans show 25,110…etc all the right mail server ports, however port 80, 443 do not show up on the external interfaces. All correct ports show up on the internal interface.

Is there a way to make this work on both interfaces, so this can act as our WebMail/External Email Gateway?

1 Like
#2

I dont have an comparable environment but this proves that apache2 by default listens on all available interfaces:

# netstat -tlpn | grep apache
tcp6       0      0 :::443                  :::*                    LISTEN      18058/apache2
tcp6       0      0 :::80                   :::*                    LISTEN      18058/apache2

The packetfilter should not block too:

# iptables -L -n | egrep "80|443"
ACCEPT     tcp  --  0.0.0.0/0            0.0.0.0/0            tcp dpt:80
ACCEPT     tcp  --  0.0.0.0/0            0.0.0.0/0            tcp dpt:443

If this is the case on your system too I’d check the “Virtualhost” configs for Apache. On my system I see "<VirtualHost *:80> and <VirtualHost *:443> which means that all available interfaces available at the time of Apache starting are used.

2 Likes
#3

I am also noticing that SSH is not responding on the external.

#4

I get the same as you on the first command, but I get nothing on the second command, just returns me to the command line.

#5

Your last command does not seem to be correct, therefore it returned nothing :frowning: It should be something like:
iptables -L -n | egrep ":80|:443"

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