Tag: Switch

Monitoring Alarm Status on Juniper EX Switches

I am in the process of installing a number of Juniper EX2200, EX3200 and EX4200 switches for a client and as part of the setup need to be able to monitor the switches for any alarms  (eg Switch Management interface down or Switch booted from Backup Partition) and have them dealt with accordingly.

Having a look at the SNMP OID tree for the EX switches I came across the following useful table

http://www.oidview.com/mibs/2636/JUNIPER-ALARM-MIB.html

Object Name Object Identifier
jnxAlarms jnxAlarms 1.3.6.1.4.1.2636.3.4
jnxCraftAlarms jnxCraftAlarms 1.3.6.1.4.1.2636.3.4.2
jnxAlarmRelayMode jnxAlarmRelayMode 1.3.6.1.4.1.2636.3.4.2.1
jnxYellowAlarms jnxYellowAlarms 1.3.6.1.4.1.2636.3.4.2.2
jnxYellowAlarmState jnxYellowAlarmState 1.3.6.1.4.1.2636.3.4.2.2.1
jnxYellowAlarmCount jnxYellowAlarmCount 1.3.6.1.4.1.2636.3.4.2.2.2
jnxYellowAlarmLastChange jnxYellowAlarmLastChange 1.3.6.1.4.1.2636.3.4.2.2.3
jnxRedAlarms jnxRedAlarms 1.3.6.1.4.1.2636.3.4.2.3
jnxRedAlarmState jnxRedAlarmState 1.3.6.1.4.1.2636.3.4.2.3.1
jnxRedAlarmCount jnxRedAlarmCount 1.3.6.1.4.1.2636.3.4.2.3.2
jnxRedAlarmLastChange jnxRedAlarmLastChange 1.3.6.1.4.1.2636.3.4.2.3.3

I have used the jnxRedAlarmCount and jnxYellowAlarmCount oid values as basic Opsview SNMP Service Checks to give me an initial overview but in the long term will be looking to combine this into a full service check script that can be used to check a number of different things.

The setup of the Service Check in Opsview is fairly simple and below are screenshots of the config that I have for each service check.

All you need to configure on your hosts is the SNMP community string and you can apply these checks individually or via a Host Template.

Once I performed a reload I could see the following in Opsview for one of my switches:

A bit of inspection showed that the Red Alarm was for the Management Interface being down (but wasnt being used on this switch) and the Yellow alarm was due to not setting a rescue configuration. I cleared the alarms by isuing the following commands

Now when I refresh the checks in Opsview I get an OK state for both checks

Juniper EX view pending changes

When making changes to Juniper EX switches yesterday I wanted to check the changes that I had made to my configuration before committing them. A quick look in the reference manual gave me the following command:

This will show the edited candidate config and pipe that into the compare function and look at the changes to the specified version (rollback 0). I could look at the changes compared to a previous config by replacing 0 with another number in the rollback sequence.

 

RANCID: Backing up Juniper EX switches

As part of my drive to backup all my switch/firewall configs I have been trying to get RANCID to backup the remaining devices on my network. The latest devices we added to the network were a pair of Juniper EX switches that are part of an iSCSI network and until now I have not had a backup of the configs. Looking at the documentation there is a set of commands to backup other JunOS devices so thought I would give it a go.

RANCID is running on an Ubuntu 10.04 server and is running version 2.3.3. and has the jlogin scripts in place. After adding the device information to the .cloginrc file I tested jlogin to check that it could connect as root to the device – it did. When I performed rancid_run however the device did not backup as expected and Rancid hung until it timed out. Upon closer inspection the issue came down to the fact that the root account will ssh to the BSD shell on the switch and not directly to the JunOS command line. To get around this I needed to setup a new user on the switches with the correct permissions and then get this to perform the backup of the switches. The command to add the config is as follows:

You will be prompted to choose a password and then confirm it before writing it to configuration

Now you can specify the details in RANCID:

The last thing that I did was to take a copy of jlogin and jrancid from an installation of RANCID 2.3.6 and everything seems to be working as expected.