BGP session wont come up after link goes down - NX-OS

[flwsterN]

Hello im doing some tests running nx-os 9000v in CML, and whenever i bring down the link running bgp between the two peers i can see in the packet capture that they do not even try to send bgp updates / hellos when enabling the interface again, its not until i reload both the switches, the bgp session goes up again. Is this some known issue or something?

[MHM Cisco World]

You use l3 interface or l2 interface with SVI to config bgp neighbor?

MHM

[flwsterN]

Hey,

Im running l3

interface Ethernet1/2
no switchport
mtu 9216
ip address 7.7.7.2/30
no shutdown

router bgp 12345
router-id 10.20.20.4
address-family ipv4 unicast
network 7.7.7.2/32
network 10.20.20.4/32
neighbor 7.7.7.1
remote-as 7
update-source Ethernet1/2
timers 3 6
address-family ipv4 unicast
weight 5
route-map LOCAL_PREF_200 in
route-map OUTGOING_AS7 out
neighbor 10.20.20.3
remote-as 12345
update-source loopback0
address-family ipv4 unicast
next-hop-self

[MHM Cisco World]

Can you draw topolgy 

I see two neighbor I need to check something by see topolgy 

MHM

[flwsterN]

whenever i reload the switches the bgp comes back up again.

as12345-sw1 bgp towards as7-sw1 conf
neighbor 7.7.7.1
remote-as 7
update-source Ethernet1/2
timers 3 6
address-family ipv4 unicast
weight 5
route-map LOCAL_PREF_200 in
route-map OUTGOING_AS7 out

as7 to as12345
neighbor 7.7.7.2
remote-as 12345
update-source Ethernet1/1
timers 3 6
address-family ipv4 unicast

[flwsterN]

AS7-sw1: Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
7.7.7.2 4 12345 399 399 0 0 0 00:03:59 Idle
AS12345-sw1:

Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
7.7.7.1 4 7 483 474 0 0 0 00:04:40 Idle

[MHM Cisco World]

Nexus# ethanalyzer local interface inband capture-filter "src host x.x.x.x"

do this in both NSK and share the output when link down 

MHM 

[flwsterN]

Hi,

Like i said in the previous post no BGP is sent. 

AS12345-sw2(config)# ethanalyzer local interface inband capture-filter "src host 7.7.7.1"
Capturing on 'ps-inb'

AS12345-sw2(config)# ethanalyzer local interface inband capture-filter "src host 7.7.7.1"
Capturing on 'ps-inb'

AS7-sw1(config-if)# ethanalyzer local interface inband capture-filter "src host 7.7.7.2"
Capturing on 'ps-inb'

[MHM Cisco World]

sorry for let reply 
I run lab and face same in eve-ng

I delete the link and BGP still show UP and debug bgp event dont show anything 

this bgp so it must direct detect the link down and also the keepalive timer is low but must work.

so I think this is bug, 
but I test shut the link and bgp is down, so try shut not remove the cable or delete it 

MHM