Windows xp with 2 gateways for redundancy?How to switch over smoothly?

[edzy55]

Hi all,

Have the above problem. I've added the second gateway to all machines via dhcp but it dosen't fail over if I drop the primary gateway connection. Is their a certain ttl or timeout before it will fail over I can reduce via group policy etc or Is their a script I can get users to run to swop the gateway in event of failure? If script wise do they have to be power users to run.

Hope someone can help.

Thanks in advance,

Edzy55

 

[linney]

Do the comments in this link about Alternate Configuration apply?

multiple Static IP's and XP home

http://groups.google.com/group/micr...ult+gateway"+xp&rnum=1&hl=en#1fcc0c43ca588fa9

 

[edzy55]

Linney

Unfortuately no, sorry I didn't make myself clear. Ok, 1 Int with 1 ip per machine. Each machine gets their ip info from a dhcp windows server which has 2 different gateways listed. We have a backup gateway with a separate line at another address on the network and is listed as a gateway in dhcp. However, to swop them over at the moment I have to move the fail over gateway up in the dhcp settings to work. Then I have to wait until all the machines dhcp lease has expired to work. Ideally I want it to just look at gateway 1 and then fail over automaticaly if it down to gateway 2.

I suppose a way around this is to take them back to statics and give them a batch file to hit to add/remove the route to the internet.

Be nice to sort this out with dhcp though. I suppose I should try to get this post moved to a more correct thread.

 

[jakechaffee]

Well even if you were to change the lease time on your server to be aroudn 10 mins (i.e. your machine checks lease at 50% so every 5 mins) it would only be for the IP and not the gateway.

I don't think there is way for DHCP to automatically move your gateway up based on one failing, that is a manual thing whether you are manually clicking a script to run or just moving the priority gateway up on the list.

Jake Chaffee
"There are 10 types of people in the world. Those who can read binary and those who can't."

 

[edzy55]

Hi Jake. The manual way we are going at the moment which works but is a bit of a mare.

However, if your correct whats the point of dhcp allowing you to put in mulitple gateways. Also, whats the point of the metric weighting option when viewing routing table. I need to test research a bit more when I get some spare time.

Thanks for your comments, must be some way to let it fail over. Maybe theirs a setting like the stupid dns cache to turn off within xp somewhere to allow the use of 2 gateways.

 

[Ash57]

Wouldnt this be more on the networking side of things? Something with a load balancer?

 

[linney]

Is this Registry Tweak applicable?

"This entry is also used in the Windows algorithm for defining non-operational (dead) gateways.

A given connection defines a gateway as dead (and switches to the next gateway in the list in stored in the value of the DefaultGateway or DhcpDefaultGateway entries) when a packet sent to the gateway must be retransmitted more than half of the number of times specified in the value of this entry. The system defines a gateway as dead when more than 25 percent of its connections have switched to the next default gateway in the list".



TcpMaxDataRetransmissions

http://technet2.microsoft.com/windo...3e55-4e9c-b0fa-52841ece2fdd1033.mspx?mfr=true

TcpMaxDataRetransmissions

http://www.microsoft.com/technet/prodtechnol/windows2000serv/reskit/regentry/58805.mspx?mfr=true

Microsoft: Windows 2003 Server

http://www.tek-tips.com/threadminder.cfm?pid=931