Add support for Juniper CHASSIS and SYSTEM alerts

[lunkwill42]

Juniper devices have a concept of alerts, classified into Chassis alerts and system alerts.

Their SNMP MIBs support fetching a number of current alerts, but no details of what the alerts actually are.

The CNaaS team wants NAV to be able to report that alerts have been flagged, but some design is needed to figure out how this should work in NAV

Also needed:

• Write new eventengine plugin to handle Juniper chassis/system alert count transitions #2432

[hmpf]

@lunkwill42 I cannot find the word "alert" in the juniper mibs, do you mean notification, trap or alarm? If not, where is this described/documented?

[lunkwill42]

@hmpf I believe you want the JUNIPER-ALARM-MIB. It simply enumerates the number of present "red" alarms and "yellow" alarms in a device. There's a copy of it here: https://github.com/pgmillon/observium/blob/master/mibs/juniper/JUNIPER-ALARM-MIB

You may want to talk to Håvard E for some guidance, as Zino actually employs this MIB (and potentially others)...

[hmpf]

Seems like step one is adding that mib to NAV's own library of mibs then :) Is there a howto for that?

[hmpf]

According to that MIB there are yellow alarms and red alarms, a count for each, whether the status is on, off or other, and a timestamp for when the status last changed. It might be relevant to mark whether these alarms are enabled or not as well (via jnxAlarmRelayMode: other, passOn, cutOff).

[lunkwill42]

Seems like step one is adding that mib to NAV's own library of mibs then :) Is there a howto for that?

Closest thing we have is this: https://nav.readthedocs.io/en/latest/hacking/adding-environment-probe-support.html?highlight=smidump#dumping-the-mib

[hmpf]

I've asked Håvard E. about what zino does about this.

The JUNIPER-ALARM-MIB only exists on equipment that has a physical craft-interface installed, supplying one actual led to show the colors, and buttons to turn monitoring on or off for various subsystems. Older stuff generally have this interface but at least MX204 and MX10003 does not. There is still a counter for these alarms though, they're just not officially accessible via SNMP.

A workaround is to have a script on the equipment that periodically reads the values (show system alarms) and makes them available via a different MIB, the Utility MIB (mib-jnx-util).

gw> show system alarms | display xml 
<rpc-reply xmlns:junos="http://xml.juniper.net/junos/19.4R0/junos">
    <alarm-information xmlns="http://xml.juniper.net/junos/19.4R0/junos-alarm">
        <alarm-summary>
            <no-active-alarms/>
        </alarm-summary>
    </alarm-information>
    <cli>
        <banner>{master}</banner>
    </cli>
</rpc-reply>

{master}
gw>

[hmpf]

When using the mib-jnx-util, zino uses the OIDs jnxUtilUintValue.82.101.100.65.108.97.114.109 for the red alarm counter and jnxUtilUintValue.89.101.108.108.111.119.65.108.97.114.109 for the yellow alarm counter.

[hmpf]

The steps so far seem to be:

• Figure out how NAV should deal with this type of value/alarm
• Add the JUNIPER-ALARM-MIB Docs
• Use the JUNIPER-ALARM-MIB if it is available on the equipment polled
• Figure out some way to get the alarms from equipment that don't support that MIB, whether via mib-jnx-util or something else.

[lunkwill42]

#2368 adds the necessary documentation for some of the command line utilities that are useful for testing SNMP OID compatibility with NAV...

[hmpf]

I've decided on making a new ipdevpoll-plugin just for these weirdos. It does not store the value, just dumps them into eventengine if not zero.

[hmpf]

If converting a mib to python with smidump with the -k flag, also increase the error level above 3 for the -l-flag.

smidump -k -l 5 -f python  ./A.mib > A.py

If it complains failed to locate MIB module foo, get the missing mibs and preload them with the -p-flag:

smidump -k -l 5 -f python  -p ./foo.mib ./A.mib > A.py