How to setup Lan & Wan etho cards

[billmckinstry]

Trying to setup a simple mail server.

Wan (mail) is by way of wireless internet into a linksys (PPPoE) 192.168.1.1 router and then only to the mailserver into etho0 192.168.1.3.

Mailserver also has etho2 192.168.1.2 connected to a switch that has 3 pc's attached and an adsl router for pc internet access.
Server does not provide proxy for pc's. Just mail.

Linksys is 192.168.1.1 and can be seen by the isp provider.

The server wan is 192.168.1.1 and can ping to 192.168.1.1 and can browse the net via linksys.

The lan connection is 192.168.1.2 and this should be visible to the pc's but it doesn't appear to be and can't ping a pc although the switch lights show it is connected.

etho0 192.168.1.3, 255.255.255.0 & default gateway 192.168.1.1

etho2 192.168.1.2, 255.255.255.0 & nothing for default gateway.

DNS is blank for hostname and primary dns is 192.168.1.1. secondary, tertiary and dns search path are all blank.

Should there be a default gateway for etho2 even though it only has a lan connection ?

If I gave it the adsl gateway then how would the server know which card to use for outside access?

Appreciate any advice

[Lazydog]

You would save yourself a lot of headaches/hair pulling if you would setup both sides to be on their own network.

eth0 192.168.1.3 255.255.255.0
eth1 192.168.10.3 255.255.255.0

The problem is your system doesn't know how to get to the inside LAN.
Does the LAN go through this box to get to the internet?

what is the output for route -n?

[billmckinstry]

route -n output is:

Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.1.0 0.0.0.0 255.255.255.255 u 1 0 0 eth0
192.168.10.0 0.0.0.0 255.255.255.255 u 1 0 0 eth2

changed ip address for eth2

Had 3 nic's - eth1 not connected to cable but have removed this card and moved the eth2 card to eth1 cards position - restarting server now.

The Lan, 3 x user pc's have get to internet by way of adsl connected to switch as 192.168.1.10.

Only the server is connected to the linksys PPPoE router 192.168.1.1

The server is connected to the Lan by eth1/2 - still resolving.

is there a way to reset all the server Nic's??

[Lazydog]

OK you are going to have to turn on forwarding on this server if the pc's are to get to the internet through this server. You are also going to want to setup a firewall to protect the server and your lan from the outside. As to reset the NIC's I do not understand what you are looking to do here.

[billmckinstry]

Thanks Lazydog. reset nic's was so I could get eth0 and eth1 instead of eth 0 & 2.
Changed setup as per attached scheme.
pc's do not go through server to reach wan.
Server just needs to be for mail only - wish it was so simple

[Lazydog]

Your NIC's are most likely tied to the MAC Addresses of the cards. Check your ifcfg-eth# and see if there are MAC Addresses listed in them.

[billmckinstry]

Resolved the old fashioned way.. Removed two nic's and reinstalled operating system.
Now with new configuration of motherboard nic and joined direct to linksys router, I am again attempting to get my "simple" mailserver to work.

Followed a web page on how to setup a simple mailserver and got all tangled up in certificates.

Why does Postfix require so many changes that mostly appear to be default in that the many reference notes I have seen all say to make the same changes so why not have these as default and then make a few??

I guess if it wasn't frustrating then we may not appreciate it so much when finished