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BGP question

Hello Everyone,

i have situation where i'm receiving a /26 subnet via CPE router and i only want to advertise /29 subnet to EBGP. is there any way to do that? i can't advertise whole /26 as it breaks other customer. Note: /29 prefix does not live on the box so i can't advertise them directly. Any help would be highly appreciated.

Note: Using Juniper MX box

so far what i did is

static {
route 24.206.51.32/29 {
receive;
no-install;
}
}
So the /29 would be in RIB but not used for forwarding decisions. i advertised /29 prefix from RIB to EBGP. but would /29 never advertised-------> didn't work this solution.

2nd try.

I create static /29 route point toward CPE and advertised /29 prefix to ebgp but again would never advertised----> didn't work

Thanks,
Jay

SOmething you're not doing right. On 1st try (first options), do a "show route advertising-protocol bgp <neighbor IP>".
I assume you have proper export policies in place, don't you ?

_________________
VPSie - SSD VPS servers in AMS-IX, LINX, DE-CIX
https://vpsie.com

Also give up the "receive" keyword. It will instruct the PFE to send all transit traffic for that route to the routing engine and, trust me, you don't want that.

_________________
VPSie - SSD VPS servers in AMS-IX, LINX, DE-CIX
https://vpsie.com

http://www.juniper.net/documentation/en_US/junos15.1/topics/reference/configuration-statement/static-edit-routing-options.html

_________________
VPSie - SSD VPS servers in AMS-IX, LINX, DE-CIX
https://vpsie.com

Yes i do have proper export policy.

show route protocol bgp advertising-protocol bgp 22.172.67.162

CPE-MGMT.L3VPN.inet.0: 13093 destinations, 26217 routes (13093 active, 0 holddown, 0 hidden)
Prefix Nexthop MED Lclpref AS path
* 22.42.182.0/25 Self 7843 20001 I
* 22.141.178.0/24 Self 7843 10796 I
* 22.205.63.0/24 Self I
* 22.212.194.0/24 Self 7843 11351 I
* 51.83.225.0/24 Self 7843 11427 I

I gave up receive command as well but it would never advertised to ebgp peer.

Yes i do have proper export policy. i gave up "receive" keyword and try to advertise again but it would never advertise to ebgp peer.

show route protocol bgp advertising-protocol bgp 22.172.57.161

CPE.L3VPN.inet.0: 19033 destinations, 21627 routes (19033 active, 0 holddown, 0 hidden)
Prefix Nexthop MED Lclpref AS path
* 22.33.172.0/25 Self 3487 40001 I
* 22.132.168.0/24 Self 3487 10697 I
* 22.206.53.0/24 Self I
* 22.203.184.0/24 Self 3487 15311 I
* 52.74.205.0/24 Self 3487 11247 I

Please post your bgp configuration, export policy as well as routing-options for the relevant VRF.

_________________
VPSie - SSD VPS servers in AMS-IX, LINX, DE-CIX
https://vpsie.com