Multiple IP addresses

[haxworthy]

Hi all,

I know in Linux you can bind multiple IP addresses to one NIC card. Does Zimbra support this type of configuration?

Any information would be greatly appreciated.

Thanks.

[viniciusfontes]

Bumping a 2008 thread. I have the exact same issue and still haven't found an answer on the Zimbra forums, wiki and Google.

Any ideas? Many thanks in advance.

[uxbod]

Welcome to the forums

It would help then if you told us what you want to achieve ?

[viniciusfontes]

I already have a working ZCS installation on production. I have only one NIC, that has a public IP address.

Now I have another Internet link and would like to use it to provide some redundancy. I have the interfaces set like this:

auto eth0
allow-hotplug eth0
iface eth0 inet static
address [myaddress1]
netmask 255.255.255.192
gateway [mygateway1]

auto eth0:1
allow-hotplug eth0:1
iface eth0:1 inet static
address [myaddress2]
netmask 255.255.255.248
gateway [mygateway2]
metric 200

I have already set the DNS records with both IP addresses, for the A and MX records. I noticed that when I access ZCS from the outside and DNS happens to resolve to the second address, I'm unable to login. No error messages, it just gets stuck on the loading screen after login.

My guess is that I need to setup something on ZCS so it's aware it has 2 IP addresses. Couldn't find any info tho.

[viniciusfontes]

So, anything on this?

[dave_kempe]

I use multiple IP addresses to login using the outlook connector or over the web (so both over http or https really) and it works fine. I use a private range for some migration tasks, and haven't had a problem with using the private IP to connect to Zimbra.

[gvocom]

This is pretty simple, you cant have 2 internet gateways on a single server, what you need to do is consult your OS documentation for adding ip's to your first NIC

In most linux distros you would look in
/etc/sysconfig/network-scripts/
take a look at ifcfg-eth0
to configure another ip create another file caled ifcfg-eth0:1 and so on and so forth.

NIC cards rarely fail, so i do not think 2 cards would provide much help in your situation, you should consider a secondary MX, some zimbra deployments consist of two heads (ZCS installations) with the zimbra clustering sofftware, and possible direct attached storage

each MX consists of a priority
in bind it would look like this

domainname.com. 14400 IN MX 10 mx1.mailserver.com
domainname.com. 14400 IN MX 20 mx2.mailserver.com

So if the first is unreachable the second would be utilized.

if you are wanting redundancy on SMTP then there is a config in the server for multiple smtp hosts that relay outgoing mail.

I hope this helps.

[fcash]

Originally Posted by gvocom

This is pretty simple, you cant have 2 internet gateways on a single server, what you need to do is consult your OS documentation for adding ip's to your first NIC

Not true. You can't have multiple default gateways in the same routing table. But it's possible to have multiple routing tables, and to select which routing table to use. In FreeBSD systems, this is done using setfib(1) and ipfw(8). In Linux systems, this is also possible, although I don't know the name of the command for creating the extra tables (never had a use for it on Linux), and using rules in iptables(8) to select them. On routers, this is part of the "source-based policy routing" features.

NIC cards rarely fail, so i do not think 2 cards would provide much help in your situation, you should consider a secondary MX, some zimbra deployments consist of two heads (ZCS installations) with the zimbra clustering sofftware, and possible direct attached storage

Having 2 separate Internet connections is handy, as it allows you to balance the outgoing traffic, and provides a redundant link in case one ISP has an outage.

[gvocom]

I guess I was assuming someone would be hosting this at a datacenter and not at home or an office, in a DC there is BGP already setup as well as other redundancies.

Routing through the OS as far as I am concerned is a waste of server resources, when you can just let the router do this. Generally that layer of the OSI model should not be handled by the server

[LMStone]

I agree with gvocom; handling multiple gateways is best done upstream on the colo provider's gear.

If you are hosting Zimbra in a home or home office with carrier-diverse Internet connectivity, then best to use a router that can handle multiple gateways and do load balancing or failover between both connections transparently to the Zimbra server. A SonicWall TZ-210 would be more than fine for an environment with less than 5Mbps to/from the Internet and costs under $1,000 including gateway anti-virus/anti-malware etc. licensing.

Sure you can light up a second NIC to do traditional teaming for redundancy/bandwidth doubling, or Active/Passive teaming to have the same MAC present to two switches (so you can survive a switch failure), but at that point you are generally in a data center of some sort and don't need a second gateway.

You can also light up a second NIC for a separate management network or iSCSI, but then again you don't need a second gateway.

Put differently, setting up a server with two gateways in our experience is a very rare and unique need; we'd rather see the need for two gateways satisfied somewhere else in the network -- not on the server.

Hope that helps,
Mark