topic Re: Will network cluster interconnect work without decnet? in Operating System - OpenVMS

Will network cluster interconnect work without decnet?

Clark Powell — Tue, 03 Nov 2009 23:28:56 GMT

I am trying to run a two node cluster with an interconnect that consists of a nic on each node connected with a tp crossover cable so that the two nics may communicate. I have not configured DECNET on these ports. I think one of the nics or the cable is bad because I can't get the second node to boot (even though it does join the cluster if I have my normal network connections from each node to our lan.) But, just to be safe I would like to ask if two nics can be the cluster interconnect even if decnet is not configured on these nics? I'm using OpenVMS 8.3

thanks
Clark Powell

Re: Will network cluster interconnect work without decnet?

Robert Gezelter — Tue, 03 Nov 2009 23:54:57 GMT

Clark,

As far as I can remember, the requirement for DECnet was removed a while ago.

I presume that the systems involved have TCP/IP configured. May I suggest that a good test would be to use an otherwise unused RFC 1918 block of addresses as a "within the cluster" subnet. Assigning these addresses to the dedicated cluster connect would allow the use of PING to verify correct functioning (when not testing, these lines could be disabled within TCP/IP).

- Bob Gezelter, http://www.rlgsc.com

Re: Will network cluster interconnect work without decnet?

Andy Bustamante — Tue, 03 Nov 2009 23:55:46 GMT

>>>an interconnect that consists of a nic on each node connected with a tp crossover cable
This is valid. By default, OpenVMS will attempt to use all NICs available for cluster traffic. The protocol for cluster traffic is SCS, which is does not require DECnet.

>>>I can't get the second node to boot (even though it does join the cluster if I have my normal network connections from each node to our lan.

If you're using a cross over cable, are both NICs configured for the same speed/duplex or auto settings?

Is this shared storage with a quorum disk? Have you confirmed the cable is a cross over cable? Are you attempting to network boot?

Andy Bustamante

Re: Will network cluster interconnect work without decnet?

Clark Powell — Tue, 03 Nov 2009 23:57:58 GMT

It was a bad cable. Works now.
Thanks all
Clark Powell

Re: Will network cluster interconnect work without decnet?

Clark Powell — Tue, 03 Nov 2009 23:59:06 GMT

Cluster communication and MSCP disk serving are funtioning now. The cable was bad.

Re: Will network cluster interconnect work without decnet?

Hoff — Wed, 04 Nov 2009 17:40:14 GMT

DECnet and SCS clustering are not particularly related.

Or more specifically, they're about as related as IP is related to clustering.

Prior to OpenVMS V6.2, it was expected that you'd have and want and use DECnet for various management tasks, but it was entirely feasible to operate and manage a cluster without DECnet around even then. (A few areas that might be useful, such as MONITOR CLUSTER, did need DECnet prior to V6.2.)

The core confusion here tends to be the use of DECnet MOP to operate satellite bootstraps. The same thing happened with MOP and DECserver downloads. if you needed MOP for various cluster or DECserver tasks, then you did (prior to V6.2) need to have DECnet around. With V6.2, LANCP became available, and MOP was this available outside of DECnet.