MC/SG polling lan card

[Decio Miname]

Does anybody knows any link explaining what protocol MC/SG uses to poll the standby interfaces? Can it be detected by a network analyzer?
TIA

[Jeff Schussele]

Hi Decio,

I'm not sure exactly what MC/SG uses, but I believe that it sends ICMP status requests on that port on the poll interval specified in the cluster config.
And yes, these will be seen by sniffers.

Rgds,
Jeff

[Duncan Edmonstone]

I don't think ICMP status requests are used for standby LANs... when they are standby they don't have a TCP/IP stack bound to them, and won't know what an ICMP request is.

As I understand it MCSG uses the Data Link Provider Interface (DLPI) which is an OSI layer 2 protocol.

for an intro take a look at the man page for lan(7). For more details look at this doc:

http://docs.hp.com/hpux/onlinedocs/B2355-90139/B2355-90139.html


HTH

Duncan

[Jeff Schussele]

Hi Duncan,

Yep, I started rethinking that as soon as I posted it.
ICMP would indeed need the stack. I *knew* it had to be at a low layer because no IP would be tied to the MAC when in standby mode.
Thanks for the clarification.

Rgds,
Jeff

[Decio Miname]

Great, Duncan. I believe I'll get to what I want from that point on. As I expected, it will be a little tricky. ;)
Thanks all!
D.

[Carsten Krege]

SG's cmcld uses dlpi polling packets to check the health of monitored LAN interfaces during normal cluster operation. cmcld sends packets using the dlpi API and adds a SNAP encapsulation (0xaa) of type cl_comm_snap (080009167e). Filtering can be done using the filter file entry:

filter type 0x167e

Carsten