Outgoing IP address

Similar Threads:

1.Setting the outgoing IP-Address

Hi all,

I'm probably missing something easy, but I have problems in choosing which
IP-Address should be used for outgoing packets (read: I don't know how to do
it). Here is the scenario:

A debian 3.0 machine with 3 ethernet interfaces, eth0 connected to the local
network, eth1 connected to provider_A using the ip-address 212.1.2.3 and
eth2 connected to provider_B using the ip-address 80.3.2.1.

I am moving from provider_A to provider_B and while the cached DNS-Entries
on some machines in the internet still point to 212.1.2.3 the machine should
respond to both network interfaces, while the defaultroute is set to eth2.

A ping to 80.3.2.1 from outside works fine, but a ping to 212.1.2.3 enters
the machine from eth1 and the echo_reply leaves through eth2 *BUT* using
212.1.2.3 as source address for the packet.

Since 212.1.2.3 is not within the network of provider_B, his routers throws
the packet away, so my ping to 212.1.2.3 won't be answered.

Is there some way to tell the IP-stack to use the address of the outgoing
interface as source under all circumstances, even if the packet is a reply
to a packet on another interface?.

Thanks,

Uli

2.Outgoing SMTP Source IP Address

3.Smart Host Relay, No DNS, outgoing mail does not contain local host IP Address

Hi All,

I am trying to configure sendmail to use smart host (MS exchange; IP:
10.10.50.50).
So, no need to use DNS, just blindly deliver all mails to mail gateway
(smart host).
Smart host works ok but I need help for:

1. how to swich off sendmail dns lookups

2. outgoing mail to NOT contain local host IP address/domain. It could
be only 127.0.0.1 but not real domain in outgoing mail:
 XXXX@XXXXX.COM 

Basicly I want to remove all information about originating host
(security requirements).


Example.

1.    May 15 12:45:32 oraprod sm-mta[18836]: [ID 801593 mail.info]
l4F8jVYt018834: to=< XXXX@XXXXX.COM >,
ctladdr=< XXXX@XXXXX.COM > (912/14), delay=00:00:01,
xdelay=00:00:00, mailer=smtp, pri=120302, relay=[] [10.10.50.50],
dsn=2.0.0, stat=Sent
( < XXXX@XXXXX.COM > Queued mail
for delivery)

2.    Message-Id:
< XXXX@XXXXX.COM >


Thank you in advance,

Angelina

4.bind outgoing mail connects to virtual ip address?

5.How to select IP address for outgoing packets?

For reasons which are not important here, I have a linux system (SuSE
9.3, if that makes any difference) which acts as the NAT router for a
LAN. This has 2 NICs, one of which connects to an ADSL router which
presents a /29 (the interface of this router is also using an address
within the /29)[1], the other connects to the internal LAN. All but 1 of
the 'external' addresses are NAT'd to various systems/services on the
LAN, with one of the external addresses being 'reserved' for services
running on the Linux system itself. In order to do this I have had to
associate 5 of the /29 addresses with the 'external' NIC using the
iproute2 tools.

I have no problems with routing incoming packets to the correct
system, nor with setting the correct outgoing IP address (using
iptables 'nat' table) for connections originating from other systems
on the LAN. 

However I have been unable to force outgoing connections from the
Linux system to use the IP address which I want. For most things this
does not matter but I have the requirement to set up a VPN, which
requires fixed endpoint addresses, from this system. I have tried
setting the source address in the 'ip route' command, but this has no
effect. I tried setting SNAT in the iptables 'nat' OUTPUT table, but
SNAT is not valid in that table.

[1] I know that this is not the best setup, but the ISP supplied the
ADSL router and we do not have access to change its configuration.

6. IP ADDRESS CHANGE ISSUES / QUESTION -Multiple IP Addresses on PDC

7. Unable to acquire IP Address or DNS, however Manual IP allows IP-IP browsing

8. IP ADDRESSING(http://mynetworkplanet.blogspot.com/2009/07/ip-address.html)