Junos OS

Hi!

I was reading in the hardening guide that it's good to set the high and full values for /var like this:

Set chassis disk-partition /var level high free-space 25 percent

Set chassis disk-partition /var level full free-space 10 percent

As I understand it, this is the threshold for when Junos will start alerting us that the disk usage is, as the command suggests, high or full.

Here's my question: How does Junos alert us? I've just done some simple testing, hoping it would be a chassis alarm, but that's not the case.

Will this show up in a log file somewhere? Is there a way to get some more proactive alerting?

Thanks

Yes there will be log messages as  well as alarms, with the alarms you can get way more proactive alerts via SNMP (email, sms, etc depending on your SNMP tool),

The alarm would be something like this,

- Minor Host 0 /var partition usage is high

Here is a document in case you ever have to deal with the issue so you can troubleshoot it,

https://kb.juniper.net/InfoCenter/index?page=content&id=KB30860&cat=QFX_SERIES&actp=LIST

I hope this is what you were looking for!

Thanks!

I can now see that it does set a chassis alarm. Takes a while for it to turn on it seems.

Here a more complet putput of what you will see in the alarms, as you can see one is Minor and the other one (when full) is Major,

root@Switch01> show system alarms
2 alarms currently active
Alarm time Class Description
2020-02-01 12:10:00 UTC Major RE 0 /var partition is full
2020-02-01 16:05:15 UTC Minor RE 0 /var partition usage is high

root@Switch01> show chassis alarms
2 alarms currently active
Alarm time Class Description
2020-02-01 12:10:00 UTC Major RE 0 /var partition is full
2020-02-01 16:05:15 UTC Minor RE 0 /var partition usage is high

Hi Luke Robertson,

Greetings, Just to add this is not supported if you are working with MX's and EX9200's, nevertheless, it will work with an ex4300 and ex4600 also you will be able to see the log/alarms using the following commands:

show log messages | match partition

show system alarms

Regards,
Lil Dexx
JNCIE-ENT#863, 3X JNCIP-[SP-ENT-DC], 4X JNCIA [cloud-DevOps-Junos-Design], Champions Ingenius, SSYB

If this solves your problem, please mark this post as "Accepted Solution" so we can help others too \:)/