Satellite/3G redundancy

Question

We have a site that currently has a satellite connection used by users, and a 3G connection used for a specific application. Connections are from different providers. Every connection has it's own router, switch and connections.

Is there a way, to move all users and servers to one switch and connect the two routers on that same switch to provide redundancy in case of one of them fails? E.g. if Satellite connectivity fails then everything will go via 3G and vice versa.

Thank you

Answer 1

there are two solution first one will be the automatic and profissional solution and need to be done from the side of your routers and the other one i consider it as a way out

first one

if both USERS and Application servers and router interfaces from the lan side run same IP range so simple you just need to configure FHRP on both router and map all your devices to single GW .

1. if you are using Cisco routers you can configure HSRP on both of them and make your devices GW the virtual IP of this HSRP
2. if you are using non cisco routers you can configure VRRP on both of your routers and also make your devices GW VRRP virtual IP

second one

if your devices and router interfaces from the lan side run same IP range , may you login to each device and configure primary and seconry GW

1. from start login to CMD as administrator then type

route add X.X.X.X mask Y.Y.Y.Y Z1.Z1.Z1.Z1 metric 10
route add X.X.X.X mask Y.Y.Y.Y Z2.Z2.Z2.Z2 metric 20
wher Xs are your lan ip range and Ys are the mask and Z1s are the primary GW and Z2s are the secondry one

2. from the interface card login to the advanced setting then configure other GW with metric 20

Answer 2

You actually have two issues :

• Determining that the link is down
• Using that information to modify your routing.

If you have a Cisco router behind the two connections, you would use IP SLA to track a remote device through each connection (typically by pinging it regularly), and then configure HSRP such that the HSRP priority on the main router is changed if ever its link goes down. Traffic will automatically move back to the main link once it's back up. See http://ciscodreamer.blogspot.fr/2009/09/ip-sla-with-hsrp.html for an example

The trick, especially on an Internet connection, is finding something that you can ping which will give you a reliable indication of whether your link is down or not, or else you will get spurious failovers.

Answer 3

Well, I am anti-Cisco solution Designer. We also have this situation around a year ago. We were using satellite backhaul for voice and data. Else, we were also connected redundant to a local operator via 3G connection. All we did is that we use a simple E1 to Ethernet convertor (Chinese converter). this converter has a DTE V.35 port for satellite and to transport this data we connect one port with VOIP gateway. As gateway was connected to data and Voice. Then for 3G connection we used the WAN port of the VOIP GW to a simple layer 2 swtich with activating the port preference. 3G and satellite were on 1+1 HSB. Then for that 3G connection we used a simple router with a SIM port on at WAN.Then we created a VPN from that remote site to the HUB site. You can use VPN of the router and get it connected to the HUB site. It is much more cheaper solution than Cisco. Its all about you skill and thinking. EVery item we used was a chinese made......