Category: junos

List trunk ports on Juniper Switch

Have you ever wanted to list the trunk ports on a Juniper EX switch? Unfortunately there doesn’t seem to exist a single dedicated command for this purpose. In the past I used to use the following command: > show ethernet-switching interfaces detail | match Trunk but this is not working on new releases. Juniper keeps
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Changes bringing interface down in Junos

I don’t know if there is any comprehensive list of changes which brings down an interface apart from specifically disabling the interface. So far I recall two of them which are striking and might not be expected to flap interface. If anyone has also experience, it might be a good place to share. per-unit-scheduler Years
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error: put-file failed on Junos

I have got the following error while I was trying to copy a file via SCP on Junos. As per the error, I thought it is something to do with my local permissions but I could read the source backup.conf file. I searched online, numerous entries showed up. yilmaz@host> file copy backup.conf scp://yilmaz@10.1.1.1:~/ yilmaz@10.1.1.1's password:
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MPLS/RSVP and BGP L3VPN #4

This post is the 4th post of my MPLS series. You can find the first three here: #1, #2 , #3 In an MPLS network, PE routers keep the site specific VPN routes inside VRF (Virtual Routing and Forwarding) tables and send the routes that they learned from CE routers to remote PE routers by
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SRX Inventory

For troubleshooting purposes I find the file /var/log/inventory quite useful. You know why? If you haven’t displayed this file so far, go and run the command >show log inventory Jan  1 00:16:44 CHASSISD release 10.4R4.5 built by builder on 2011-05-06 06:19:27 UTC Jan 1 00:16:44 FPC - part number 750-111111, serial number ATXXXXXXX With this
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scripting commands in junos

One of the things that I need during troubleshooting sessions is to run a specific command at regular intervals. Instead of doing this manually you can create a tiny script to run your command every second for you. Here is how you can do it; while [ 1 ] do cli -c "show route receive-protocol
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Configuring virtual router

I just want to talk about briefly how you can configure a simple virtual router in Junos. For this I have drawn a physical and a logical view of my simple topology. In physical view, you can see that there is only one SRX but logically there are actually one virtual router connected from interface
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Junos per packet load balancing

If you have two multiple equal cost paths to the same destination, JunOS behavior is to pick up one of the next-hops and use that one. For example in the following scenario, Junos keeps sending the packets via the ge-0/0/0.41 interface. root@R4> show route 172.16.1.0 inet.0: 7 destinations, 7 routes (7 active, 0 holddown, 0
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