cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
1710
Views
0
Helpful
9
Replies

send community question

julxu
Level 1
Level 1

Hi expert

I have configured send community statement in my bgp router like:

router bgp nnnnn

.....

neighbor 111.111.111.111 send-community both

neighbor 111.111.111.111 route-map out-to-isp out

.....

route-map out-to-isp permit 10

match ip address 222.222.222.222

set community xxxx:80

when I check sh ip bgp ipv4 unicast 111.111.111.111 and it said:

community: no-export

can I get advice? how can I check if I have succesful send commutiy string out?

many regards

julxu

4 Accepted Solutions

Accepted Solutions

nkarpysh
Cisco Employee
Cisco Employee

Hello,

first of all be clear that in route-map match ip address statement matching by the ACL name and not the ip address itself. So in your case

match ip address 222.222.222.222

means match ACL with name 222.222.222.222 and you need to have one matching your traffic.

Next to check if community is send and received check "show ip bgp nei 111.111.111.111 advertise" and surely check "show ip bgp " for routes for which you have changed the community.

Nik

HTH,
Niko

View solution in original post

On the neighbor you can do:

sh ip bgp A.B.C.D - where A.B.C.D is the route for which community should be set. Or you can do "sh ip bgp community xxx:80" - it will show which routes are set with this community - also on remote neighbor.

On the current router - you can check the advertised routes with the command I gave above.

Nik

HTH,
Niko

View solution in original post

It means that no community is attached - check if your access-list 222.222.222.222 matching a correct route.

Nik

HTH,
Niko

View solution in original post

For the bgp route that shows metric 44... is it a redistributed route from OSPF to BGP?

View solution in original post

9 Replies 9

nkarpysh
Cisco Employee
Cisco Employee

Hello,

first of all be clear that in route-map match ip address statement matching by the ACL name and not the ip address itself. So in your case

match ip address 222.222.222.222

means match ACL with name 222.222.222.222 and you need to have one matching your traffic.

Next to check if community is send and received check "show ip bgp nei 111.111.111.111 advertise" and surely check "show ip bgp " for routes for which you have changed the community.

Nik

HTH,
Niko

Nik

thanks for the reply

I can see the route, but, I still do not sure what communite it used. how can I check if the community is 80 which I have sent?

Many Regards

julxu

On the neighbor you can do:

sh ip bgp A.B.C.D - where A.B.C.D is the route for which community should be set. Or you can do "sh ip bgp community xxx:80" - it will show which routes are set with this community - also on remote neighbor.

On the current router - you can check the advertised routes with the command I gave above.

Nik

HTH,
Niko

show ip bgp community give no any information, and

#sh ip bgp community xxxx:80

#

sh ip bgp a.b.c.d and do not give community string.

It means that no community is attached - check if your access-list 222.222.222.222 matching a correct route.

Nik

HTH,
Niko

yes, it is:

the route-map out-to-isp permit 10

match ip address prefix-list test

set community xxxx:80

ip prefix-list test seq 5 333.333.333.0/24

ip prefix-list test seq 10 444.444.444.0/24

and actually, I can get the routes, that means routes part is working, only stringy thing is the community do not send out?

and one more strangy thing is there is metric 44 I can see.

when I do sh ip bgp xxx.xxx.xxx.xxx ( ISP site) it says: metric 44, but I have not set metric 44 myself.

For the bgp route that shows metric 44... is it a redistributed route from OSPF to BGP?

ok, there is no problem now. the meric 44, yes, it is OSPF to BGP, the community I can not see, but, ISP side can see.

just I do not know how to check on my machine to confirm. I did send correnct community string.

Thanks for all the comments.

You can't verify the community from the router implementing the community as the information is injected into the prefix as it leaves the router. Same concept when using AS_PATH prepend, you can't verify the additional AS_PATH information from the router itself.

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: