Configuring failover with multiple connections

[gmmastros]

Please forgive me, I'm an accidental network admin. My primarily role is DBA and occasional programmer. Unfortunately, we don't have a network admin, so I am stuck in very unfamiliar territory.

Small company with 2 internet connections (separate providers). Each internet connection has a static IP address. I want to set things up so that one internet connection acts as a failover for the other. We host websites, terminal services, and other webservices internally.

My preference would be to configure the system so that one connection handles to terminal services connection but also acts as a failover for the other connection. The other connection would handle the websites and webservices, but would act as a failover for the terminal services connection.

I currently own a relatively low end (think inexpensive) cisco router that I am using for one of the connections. The other internet connection is currently unused.

I realize I will need to purchase hardware, and I have no problem with this. I would welcome recommendations regarding hardware purchases.

I currently have things configured with my domain name provider for one of the static ip addresses, but I have no idea how I could configure failover ip addresses with the domain name provider.

Any advise is appreciated.

-George
Microsoft SQL Server MVP
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[VinceWhirlwind]

Does your existing router have a spare interface for the 2nd ISP connection?

The easy (but slightly less smooth) way to do it is just to have two default routes on your router, with the less desirable one given a higher cost. If a fault develops at your 1st ISP, you can unplug it and the 2nd will take over. That gives you and active/passive setup.

As for allowing terminal services traffic in on one and other traffic on the other....the problem with that is that the device receiving those connections will need to be listening via one ISP or the other. The only way it can do both is if something in your gateway environment (your router or further out at the ISP) does source NAT on the incoming connections, so your hosts can reply to the correct place. You can have a static route identifying the NATd source address location to allow your host to respond. Both ISPs would need to be setup to receive these connections, and you won't get them to failover to each other, so your remote clients would need to have both connection details so they can try the first one if the second one doesn't work.

Sorry, those are a few thoughts anyway.

 

[gmmastros]

[tt][blue]Does your existing router have a spare interface for the 2nd ISP connection?[/blue][/tt]

No. I suspect I need to purchase a dual wan router. Any suggestions?

I'm still confused about the domain configuration. At my domain name registrar, I have:

saas.mydomainname.com forwarding to ip address 111.111.111.111
mydomain.com forwarding to ip address 111.111.111.111

If the internet connection serving 111.111.111.111 goes down, how would traffic automatically failover to 222.222.222.222 ? Would this somehow be handled by the dual wan router?

-George
Microsoft SQL Server MVP
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"The great things about standards is that there are so many to choose from." - Fortune Cookie Wisdom

 

[tphethai]

Hot Standby Routing Protocol or HSRP, is a Cisco proprietary protocol that allows two or more routers to work together to represent a single IP address for a particular network. HSRP, as well as Virtual Route Redundancy Protocol (VRRP) are considered high-availability network services that allow for almost immediate fail over to a secondary interface when the primary interface becomes unavailable.

I think you can see the flash presentation below that good explain about path fail over both one router or two routers...
check this out: HSRP Design/Concept

 

[stubnski]

Hi,
Are you using a routing protocol(BGP, eigrp, OSPF) or just a static route?

Since you are not a network admin I would suggest you contact your main ISP and tell them what you want to do and have them give you suggestions since they probably have setups like yours at other customer sites.

 

[gmmastros]

Since I don't know what BGP, eigrp, or OSPF is, I guess we are using a static route.

Contacting the main ISP is a good suggestion. I'll do that.

Thanks.

-George
Microsoft SQL Server MVP
My Blogs
SQLCop
twitter
"The great things about standards is that there are so many to choose from." - Fortune Cookie Wisdom