[ofa-general] opensm --lcm

[Bernd Schubert]

Hi,

so far we always did run opensm without the --lmc option, but just recently I 
read in opensm's manpage about it.

<opensm manpage>
This option specifies the subnet's LMC value.  The number of LIDs assigned to 
each port  is  2^LMC.   
The LMC  value  must be in the range 0-7.  LMC values > 0 allow multiple paths 
between ports.  LMC values > 0 should only be used if the subnet topology 
actually provides multiple paths between ports, i.e.  multiple
interconnects  between  switches.   Without -l, OpenSM defaults to LMC = 0, 
which allows one path between any two ports.
</opensm manpage>

In one of our configurations we do have a mts2400 (master) switch and 
connected to it are two mts14400 switches (each with 3 connections to the the 
mts2400).
I think from the description of the opensm manpage we need to give the "--lmc" 
to make use of the 3 connections from each mts14400 switch to the mts2400 
switch, don't we?
Furthermore, from manpage I would think we even need this 
option for proper inter-communication between the switch modules?


Thanks in advance,
Bernd

-- 
Bernd Schubert
Q-Leap Networks GmbH