Configure BGP-Specific Options
Purpose
When unexpected events or problems occur, or if you want to diagnose BGP establishment issues, you can view more detailed information by configuring options specific to BGP. You can also configure tracing for a specific BGP peer or peer group. For more information, see the Junos System Basics Configuration Guide.
Display Detailed BGP Protocol Information
Action
To display BGP protocol information in detail, follow these steps:
- In configuration mode, go to the following hierarchy level:[edit]user@host# edit protocol bgp traceoptions
- Configure the flag to display
detailed BGP protocol messages:[edit protocols bgp traceoptions]user@host# set flag update detail
- Verify the configuration:user@host# show
For example:
[edit protocols bgp traceoptions]user@host# show flag update detail; - Commit the configuration:user@host# commit
- View the contents of the file containing the detailed
messages:user@host# run show log filename
For example:
[edit protocols bgp traceoptions]user@pro5-a# run show log bgp Sep 17 14:47:16 trace_on: Tracing to "/var/log/bgp" startedSep 17 14:47:17 bgp_read_v4_update: receiving packet(s) from 10.255.245.53 (Internal AS 10458)Sep 17 14:47:17 BGP RECV 10.255.245.53+179 -> 10.255.245.50+1141Sep 17 14:47:17 BGP RECV message type 2 (Update) length 128Sep 17 14:47:17 BGP RECV flags 0x40 code Origin(1): IGPSep 17 14:47:17 BGP RECV flags 0x40 code ASPath(2): 2Sep 17 14:47:17 BGP RECV flags 0x80 code MultiExitDisc(4): 0Sep 17 14:47:17 BGP RECV flags 0x40 code LocalPref(5): 100Sep 17 14:47:17 BGP RECV flags 0xc0 code Extended Communities(16): 2:10458:1[...Output truncated...]
Meaning
Table 1 lists tracing flags specific to BGP and presents example output for some of the flags. You can also configure tracing for a specific BGP peer or peer group. For more information, see the Junos System Basics Configuration Guide.
Table 1: BGP Protocol Tracing Flags
Tracing Flags | Description | Example Output |
|---|---|---|
aspath | AS path regular expression operations | Not available. |
damping | Damping operations | Nov 28 17:01:12 bgp_damp_change: Change event |
keepalive | BGP keepalive messages | Nov 28 17:09:27 bgp_send: sending 19 bytes to 10.217.5.101 (External AS 65471) |
open | BGP open packets | Nov 28 18:37:42 bgp_send: sending 37 bytes to 10.217.5.101 (External AS 65471) |
packets | All BGP protocol packets | Sep 27 17:45:31 BGP RECV 10.0.100.108+179 -> 10.0.100.105+1033 |
update | Update packets | Nov 28 19:05:24 BGP SEND 10.217.5.1+179 -> 10.217.5.101+55813 |
Diagnose BGP Session Establishment Problems
Purpose
To trace BGP session establishment problems.
Action
To trace BGP session establishment problems, follow these steps:
- In configuration mode, go to the following hierarchy level:[edit] user@host# edit protocol bgp
- Configure BGP open messages:[edit protocols bgp]user@host# set traceoptions flag open detail
- Verify the configuration:user@host# show
For example:
[edit protocols bgp]user@host# show traceoptions { file bgplog size 10k files 10; flag open detail;} - Commit the configuration:user@host# commit
- View the contents of the file containing the detailed
messages:user@host#run show log filename
For example:
[edit protocols bgp]user@hotst# run show log bgplogSep 17 17:13:14 trace_on: Tracing to "/var/log/bgplog" started
Sep 17 17:13:14 bgp_read_v4_update: done with 201.0.0.2 (Internal AS 10458) received 19 octets 0 updates 0 routes
Sep 17 17:13:15 bgp_read_v4_update: receiving packet(s) from 201.0.0.3 (Internal AS 10458)
Sep 17 17:13:15 bgp_read_v4_update: done with 201.0.0.3 (Internal AS 10458) received 19 octets 0 updates 0 routes
Sep 17 17:13:44 bgp_read_v4_update: receiving packet(s) from 201.0.0.2 (Internal AS 10458)
[...Output truncated...]
