SQL Server Performance Forum – Threads Archive

SQL Server Cluster Heart-Beat Cross-Over?

When I was reading the SQL Cluster deployment document from MSIB 2.5 http://www.microsoft.com/downloads/…78-1FFA-4E6C-9AB0-D209B702DF45&displaylang=en) It says that Â¡K. Â¡P Do not connect the SQL Server computers using a crossover cable; use a switch or hub instead. Does anybody know why not using crossover for heart-beat?
I was asking around and I got response that … "Before installing a cluster using a shared storage network, you would be turning off the other machine in the cluster. If you use a crossover cable, the other NIC for heartbeat would not be detected at all as connected in the first machine. If its connected to a hub we would detect that NIC even if the other machine is down and continue with the cluster configuration. Otherwise there is a registry setting to work around this." Does anybody know which registry to set this up? Thanks a lot. Po-Shan.

You can use serial port or non-dedicated NIC for heartbeat Communication between Server Cluster nodes is critical for smooth cluster operations. Therefore, you must configure the networks that you use for cluster communication are configured optimally and follow all hardware compatibility list requirements. Satya SKJ
Moderator
http://www.SQL-Server-Performance.Com/forum
This posting is provided â€œAS ISâ€ with no rights for the sake of knowledge sharing.

It is just saying that during the configuration of the first node the second node should be down. Some network cards won’t show a link if the server is turned off, which means that when you install clustering on node 1 it won’t see a link on the heartbeat nic, and so won’t display it as a NIC able to be used in clustering. On most servers it is fine, since modern servers still leave power going to the NIC when the server is switched off (for WOL), and you can start the second server but interrupt the boot process, e.g. press F8 just as Windows tries to load to get the boot option menu. This should be enough to get a link between the servers Cheers
Twan

We use crossover cables for all of our clusters, and for our particular hardware configuration, we have never had any issues. —————————–
Brad M. McGehee, MVP
Webmaster
SQL-Server-Performance.Com

A cross-over cable should be sufficient for a two node cluster. Remember that the switch/hub does an internal "cross-over" of the straight cable(s) that you use. You WILL definitely want to use a switch/hub for a three or four node cluster. Nathan H.O.
Moderator
SQL-Server-Performance.com

]]>