Hi Tom,

Does it only happen on the 100G ports? If you do a single port as VLT does it still have performance issues?

I tried to shutdown one of the 2 ports on VLT and one port on the portchannel but results are the same.

I have a very simple configuration:

2 dell switches with VTL and a port channel to a nexus.

Here is my configuration

On both switches:

interface ethernet1/1/53
description VLTi
no shutdown
no switchport
flowcontrol receive off
flowcontrol transmit off

interface ethernet1/1/54
description VLTi
no shutdown
no switchport
flowcontrol receive off
flowcontrol transmit off

ONSWITCH DELL 1:

!
vlt-domain 101
backup destination 172.17.255.66
discovery-interface ethernet1/1/53-1/1/54
primary-priority 4096
vlt-mac 00:11:22:33:44:55
!
interface port-channel50
description LinktoCisco
no shutdown
switchport mode trunk
switchport trunk allowed vlan 113
mtu 9216
vlt-port-channel 50

interface mgmt1/1/1
no shutdown
no ip address dhcp
ip address 172.17.255.65/29

interface vlan113
description Test
no shutdown
mtu 9216
ip address 172.17.0.31/23

ON SWITCH DELL2

!
vlt-domain 101
backup destination 172.17.255.65
discovery-interface ethernet1/1/53-1/1/54
primary-priority 8192
vlt-mac 00:11:22:33:44:55
!
interface port-channel50
description LinktoCisco
no shutdown
switchport mode trunk
switchport trunk allowed vlan 113
mtu 9216
vlt-port-channel 50

interface mgmt1/1/1
no shutdown
no ip address dhcp
ip address 172.17.255.66/29

interface vlan113
description Test
no shutdown
mtu 9216
ip address 172.17.0.32/23

Ping from dell swith 2 to dell switch 1

DellA2# ping 172.17.0.31
PING 172.17.0.31 (172.17.0.31) 56(84) bytes of data.
64 bytes from 172.17.0.31: icmp_seq=1 ttl=64 time=5.01 ms
64 bytes from 172.17.0.31: icmp_seq=2 ttl=64 time=4.05 ms
64 bytes from 172.17.0.31: icmp_seq=3 ttl=64 time=2.88 ms
64 bytes from 172.17.0.31: icmp_seq=4 ttl=64 time=9.91 ms
64 bytes from 172.17.0.31: icmp_seq=5 ttl=64 time=8.20 ms
64 bytes from 172.17.0.31: icmp_seq=6 ttl=64 time=6.79 ms
^C
--- 172.17.0.31 ping statistics ---
6 packets transmitted, 6 received, 0% packet loss, time 5006ms
rtt min/avg/max/mdev = 2.889/6.144/9.911/2.420 ms

Switch 2 to self address:

DellA2# ping 172.17.0.32
PING 172.17.0.32 (172.17.0.32) 56(84) bytes of data.
64 bytes from 172.17.0.32: icmp_seq=1 ttl=64 time=0.056 ms
64 bytes from 172.17.0.32: icmp_seq=2 ttl=64 time=0.044 ms
64 bytes from 172.17.0.32: icmp_seq=3 ttl=64 time=0.159 ms
64 bytes from 172.17.0.32: icmp_seq=4 ttl=64 time=0.041 ms
64 bytes from 172.17.0.32: icmp_seq=5 ttl=64 time=0.063 ms
64 bytes from 172.17.0.32: icmp_seq=6 ttl=64 time=0.046 ms
^C
--- 172.17.0.32 ping statistics ---
6 packets transmitted, 6 received, 0% packet loss, time 5100ms
rtt min/avg/max/mdev = 0.041/0.068/0.159/0.041 ms

same problem from switch 1.

Do you wnat me to test VLT on 25Gb ports ?

Thanks

Tom.

Yes, please try that.