obtain connectx interface ifSpeed via SNMP

Infrastructure & Networking Adapters and Cables InfiniBand/VPI Adapter Cards
1

Hello

I try to obtain via SNMP the speed of an interface of type infiniband

Here is what I’ve done:

snmpget -v 2c -c public t26 ifDescr.9 ifType.9 ifSpeed.9

IF-MIB::ifDescr.9 = STRING: ib0

IF-MIB::ifType.9 = INTEGER: infiniband(199)

IF-MIB::ifSpeed.9 = Gauge32: 0

ifSpeed is not correct.

ibstat or ibstatus give me the right value :

ssh t28 ibstatus | grep rate

rate: 100 Gb/sec (4X EDR)

Is there a private MIB to get the right value ?

Thanks

2

Query is directed at host where the MELLANOX HCA is installed. Host runs linux centos 7 net-snmp agent. I can obtain ifDescr (ib0) or ifType (infiniband) but ifSpeed and ifXHighSpeed are returned as zero.

Host is direct connected with another one (no switch)

Thanks

3

speed is not currently populated in agent. Look at net-snmp / Code / [40c09d] /agent/mibgroup/if-mib/data_access/interface_linux.c net-snmp / Code / [0d3c27] /agent/mibgroup/if-mib/data_access/interface_linux.c

You can see there’s routine netsnmp_linux_interface_get_if_speed which is conditionally compiled depending on ethtool but it’s only called for ifTypes of IANAIFTYPE_ETHERNETCSMACD.

Currently, it looks like it calls netsnmp_access_interface_entry_guess_speed which is in interface.c which is:

void

netsnmp_access_interface_entry_guess_speed(netsnmp_interface_entry *entry)

{

if (entry->type == IANAIFTYPE_ETHERNETCSMACD)

entry->speed = 10000000;

else if (entry->type == IANAIFTYPE_SOFTWARELOOPBACK)

entry->speed = 10000000;

else if (entry->type == IANAIFTYPE_ISO88025TOKENRING)

entry->speed = 4000000;

else

entry->speed = 0;

entry->speed_high = entry->speed / 1000000LL;

}

so speed is 0.

Are you building your own agent ? If so, I’ll dig a little deeper on this.

4

Precision : ifHighSpeed give the same zero value (100000 expected for EDRX4).

5

Is the SNMP query directed at a host or managed switch ? What is the SNMP agent being used on the host or the managed switch ?

6

Thanks for your response and suggestion

My need is integration in supervision platform (Nagios).

I’ve done it (read and display connection speed) by Nagios NRPE + ibstat commands.

But I would like to implement by the standard SNMP way.

I was surprised to see SNMP agent does not return the correct value, as ethtool (or ibstat) do.

Tests :

[root@t25 ~]# snmpget -c public -v 2c localhost ifType.9

IF-MIB::ifType.9 = INTEGER: infiniband(199)

[root@t25 ~]# snmpget -c public -v 2c localhost ifDescr.9

IF-MIB::ifDescr.9 = STRING: ib0

[root@t25 ~]# snmpget -c public -v 2c localhost ifHighSpeed.9

IF-MIB::ifHighSpeed.9 = Gauge32: 0

[root@t25 ~]# ethtool ib0 | grep Speed

Speed: 100000Mb/s

Shouldn’t agent procedure netsnmp_linux_interface_get_if_speed_mii(…) in net-snmp / Code / [21b005] /agent/mibgroup/if-mib/data_access/interface_linux.c https://sourceforge.net/p/net-snmp/code/ci/master/tree/agent/mibgroup/if-mib/data_access/interface_linux.c#l1008 return the correct value ?

Unfortunately, I don’t have the necessary skills or experience to modify the code of the agent…

Regards