Category: mpls

Traceroute behaviour in MPLS

Traceroute is a great tool to discover the path a packet traverses in outgoing direction but if you have an MPLS cloud, you may have some unexpected behavior if you don’t do some tweaks. First of all let’s see how traceroute discovers a path when there isn’t any MPLS cloud. The network above is using
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Layer 2 Circuit on SRX

I will briefly show how you can set up Layer 2 circuit between two packet-mode SRX boxes on 12.1X46-D10 release. Simply, if you set up a Layer 2 circuit between two sites, you can connect the same subnet between two different geographic location over an MPLS cloud. Look at the following sample topology and assume
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BGP L3VPN with Flow services

This is the 5th and final post of my MPLS series. You can find all posts under mpls-tutorial tag. So far I have run all SRX devices in packet mode which means we weren’t able to use service features of SRX firewall. With this new config, we can also inspect the traffic. You can find
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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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MPLS/RSVP configuration & troubleshooting #3

This is the 3rd post of my MPLS/RSVP series. In the first and second, I set up an MPLS cloud with some sort of redundancy. In this post, I will enable traffic engineering support on OSPF in order to use CSPF and fast reroute feature. To explain fast reroute I need the topology again; In
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MPLS label allocation failure

I was playing with a test MPLS network today and I saw that my LSP isn’t UP. ¬†When I checked with the show mpls command , I have seen the following “MPLS label allocation failure” message. Then I checked the 192.168.23.1 router to troubleshoot the issue. The issue was again I forgot to enable mpls
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