The following
example shows how to disable TCP path MTU discovery for all sessions. Use the
show
ip
bgp
neighbors command to verify that TCP path MTU
discovery has been disabled.
router bgp 65535
no bgp transport path-mtu-discovery
bgp log-neighbor-changes
neighbor 3.3.3.3 remote-as 65535
neighbor 3.3.3.3 update-source Loopback0
!
address-family vpnv4
neighbor 3.3.3.3 activate
neighbor 3.3.3.3 send-community extended
exit-address-family
Router# show ip bgp neighbors
BGP neighbor is 3.3.3.3, remote AS 65535, internal link
BGP version 4, remote router ID 3.3.3.3
BGP state = Established, up for 00:00:13
Last read 00:00:12, last write 00:00:13, hold time is 180, keepalive interval is 60 seconds
Neighbor sessions:
1 active, is not multisession capable (disabled)
Neighbor capabilities:
Route refresh: advertised and received(new)
Four-octets ASN Capability: advertised and received
Address family IPv4 Unicast: advertised and received
Address family VPNv4 Unicast: advertised and received
Enhanced Refresh Capability: advertised and received
Multisession Capability:
Stateful switchover support enabled: NO for session 1
Message statistics:
InQ depth is 0
OutQ depth is 0
Sent Rcvd
Opens: 1 1
Notifications: 0 0
Updates: 2 2
Keepalives: 2 2
Route Refresh: 0 0
Total: 5 5
Default minimum time between advertisement runs is 0 seconds
For address family: IPv4 Unicast
Session: 3.3.3.3
BGP table version 1, neighbor version 1/0
Output queue size : 0
Index 8, Advertise bit 0
8 update-group member
Slow-peer detection is disabled
Slow-peer split-update-group dynamic is disabled
Interface associated: (none)
Sent Rcvd
Prefix activity: ---- ----
Prefixes Current: 0 0
Prefixes Total: 0 0
Implicit Withdraw: 0 0
Explicit Withdraw: 0 0
Used as bestpath: n/a 0
Used as multipath: n/a 0
Outbound Inbound
Local Policy Denied Prefixes: -------- -------
Total: 0 0
Number of NLRIs in the update sent: max 0, min 0
Last detected as dynamic slow peer: never
Dynamic slow peer recovered: never
Refresh Epoch: 1
Last Sent Refresh Start-of-rib: never
Last Sent Refresh End-of-rib: never
Last Received Refresh Start-of-rib: never
Last Received Refresh End-of-rib: never
Sent Rcvd
Refresh activity: ---- ----
Refresh Start-of-RIB 0 0
Refresh End-of-RIB 0 0
For address family: VPNv4 Unicast
Session: 3.3.3.3
BGP table version 1, neighbor version 1/0
Output queue size : 0
Index 7, Advertise bit 0
7 update-group member
Slow-peer detection is disabled
Slow-peer split-update-group dynamic is disabled
Interface associated: (none)
Sent Rcvd
Prefix activity: ---- ----
Prefixes Current: 0 0
Prefixes Total: 0 0
Implicit Withdraw: 0 0
Explicit Withdraw: 0 0
Used as bestpath: n/a 0
Used as multipath: n/a 0
Outbound Inbound
Local Policy Denied Prefixes: -------- -------
Total: 0 0
Number of NLRIs in the update sent: max 0, min 0
Last detected as dynamic slow peer: never
Dynamic slow peer recovered: never
Refresh Epoch: 1
Last Sent Refresh Start-of-rib: never
Last Sent Refresh End-of-rib: never
Last Received Refresh Start-of-rib: never
Last Received Refresh End-of-rib: never
Sent Rcvd
Refresh activity: ---- ----
Refresh Start-of-RIB 0 0
Refresh End-of-RIB 0 0
Address tracking is enabled, the RIB does have a route to 3.3.3.3
Connections established 8; dropped 7
Last reset 00:00:13, due to Peer closed the session of session 1
Transport(tcp) path-mtu-discovery is disabled
Graceful-Restart is disabled
SSO is disabled
Connection state is ESTAB, I/O status: 1, unread input bytes: 0
Connection is ECN Disabled, Mininum incoming TTL 0, Outgoing TTL 255
Local host: 1.1.1.1, Local port: 179
Foreign host: 3.3.3.3, Foreign port: 20089
Connection tableid (VRF): 0
Maximum output segment queue size: 50
Enqueued packets for retransmit: 0, input: 0 mis-ordered: 0 (0 bytes)
Event Timers (current time is 0x4CBC07BC):
Timer Starts Wakeups Next
Retrans 4 0 0x0
TimeWait 0 0 0x0
AckHold 4 1 0x0
SendWnd 0 0 0x0
KeepAlive 0 0 0x0
GiveUp 0 0 0x0
PmtuAger 0 0 0x0
DeadWait 0 0 0x0
Linger 0 0 0x0
ProcessQ 0 0 0x0
iss: 2825924659 snduna: 2825924815 sndnxt: 2825924815
irs: 683352676 rcvnxt: 683352832
sndwnd: 16229 scale: 0 maxrcvwnd: 16384
rcvwnd: 16229 scale: 0 delrcvwnd: 155
SRTT: 413 ms, RTTO: 3205 ms, RTV: 2792 ms, KRTT: 0 ms
minRTT: 0 ms, maxRTT: 1000 ms, ACK hold: 200 ms
uptime: 13472 ms, Sent idletime: 12248 ms, Receive idletime: 12448 ms
Status Flags: passive open, gen tcbs
Option Flags: nagle
IP Precedence value : 6
Datagrams (max data segment is 536 bytes):
Rcvd: 10 (out of order: 0), with data: 5, total data bytes: 155
Sent: 9 (retransmit: 0, fastretransmit: 0, partialack: 0, Second Congestion: 0), with data: 5, total data bytes: 155
Packets received in fast path: 0, fast processed: 0, slow path: 0
fast lock acquisition failures: 0, slow path: 0
TCP Semaphore 0x3CCE2D54 FREE