Category: junos

Layer 2 loop troubleshoothing

Check that stupid interface statistics first if things are god damn wrong One network guy says I thought it is better to write the summary of the ports first. I have had multiple layer 2 loops in my career and they were mostly disastrous. I think there is nothing more scary than a layer 2
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PXE for network engineers

As a network engineer, you might receive a request from your colleagues probably Desktop team to configure network devices for PXE server. If you don’t know what PXE, how it works and configured, I will try to answer those questions on this post. Mostly I will focus on Windows imaging which I mostly configured devices
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Juniper SNMPv2 on routing instance

When I need to configure SNMPv2 on a Juniper device and routing instance is involved, I always forget to enable some knobs. Here is a quick one which allowed me to query an EX switch through its VR (in my example VR name is ISP1). You can also specify your specific VR name under “routing-instance-access”
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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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