Junos
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Junos

gre with vrf

‎07-23-2019 10:46 PM

Hi Experts,

 

I've an issue running gre on the main when my tunnel and destination IPs for the gre sits in a vrf. 

I've no issue setting it up if the source and destination IP sits on main. 

This is my scenario:

mx480 (LA) <-----GRE Over Carrier(lets assume carrier A in this case)----> MX480 (Tokyo)

 

So, i've Carrier A transit connected to MX in LA and in Tokyo and i which this carrier A is sitting in a vrf in both location respectively. 

If i were to move this carriers back to main, then i have no issue as the gre is pingable and OSPF works perfectly fine but the problem starts when i move the Carrier A into the vrf. 

I've a default route to next-table inet.0 in the respective vrf and rib-group to copy the routes inside the vrf back to main (for testing i copy all routes from vrf to main).
I've also tried moving the gre interface into the vrf and also add "tunnel destination routing-instace " but no luck.

Below would be my config:
Gre at LA:

unit 9 {
description "GRE DEGUG TEST";
tunnel {
source x.x.x.x; --> SITS inside VRF called P1 (LOCAL ROUTE of CARRIER A )
destination y.y.y.y; --> SITS inside VRF as well at Tokyo side called P1 (LOCAL ROUTE of CARRIER A )
}
family inet {
mtu 1476;
tcp-mss 1436;
address 10.54.130.33/30;
}
}

GRE at Tokyo 

unit 9 {
tunnel {
source y.y.y.y;
destination x.x.x.x;
}
family inet {
mtu 1476;
tcp-mss 1436;
address 10.54.130.34/30;
}
}

PLease advise 

3 REPLIES 3
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Junos

Re: gre with vrf

‎07-24-2019 12:26 AM

Hi,

 

With the tunnel IP's in the VRF, gr interface in the VRF and the carrier in the VRF too, can you try configuring the below commands on both the locations.

 

set interface gr-0/0/0 unit 0 tunnel routing-instance destination <routing-instance-name> -> (Routing instance to reach the tunnel destination.)
set routing-instances <name> routing-options static route <tunnel dest IP> next-table <routing-table-name>

 

Let me know if this works. 

 

Regards,

Pradeep Kumar.

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Junos

Re: gre with vrf

‎07-24-2019 02:26 AM

Hi Pradeep,

 

Thanks for the input. i've tried to config before but when i put routing-instance destination statement onto the gre it breaks the gre tunnel where gre interface goes down. 

I'm still thinking on how to make it work. It's very weird. 

 

Thanks

 

Highlighted
Junos

Re: gre with vrf

‎07-24-2019 09:29 AM

Hello,

I'll say let's start with basic test.  In order for GRE tunnel to come up the tunnel destination should be rachable from tunnel source. So, after you try each step, like next-table, rib-group etc, please check following three things.

I think once you have all of these working on both the router LA and Tokyo tunnel should come up

1) Check if the source IP is in the routing-instance as direct/local route

show route x.x.x.x

2) Check if the destination IP is in the routing-instance, you may use rib-group to leak this route from main to routing-instance

show route y.y.y.y

3) Ping the tunnel destination with tuneel source from the routing-instance and confrim if it works

ping y.y.y.y source x.x.x.x routing-instance <name>

If ping doesn't work see where its getting borken:

a) veirfy if other traffic is working or not telnet y.y.y.y source x.x.x.x routing-instance <>
b)  traceroute can be done, traceroute y.y.y.y source x.x.x.x routing-instance <>

Please accept my reply as solution if it solves your query, Kudos a appreciated too.

thanks
Vishal




 

 

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