Flapping on Cisco switch when connected to Extreme Wireless Controller lag2 ports

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On my C5210 Extreme Wireless Controller, I have a lag2 which consists of esa2 and esa3. These are filled with fiber SFP's which connect to a Cisco C3750 (ports 51, and 51 on a 48 port switch).

On my Cisco side, I am seeing MAC flapping between the two lag ports ...
.Mar  9 14:52:19.071: %SW_MATM-4-MACFLAP_NOTIF: Host 001e.67d0.5b54 in vlan 72 is flapping between port Gi1/0/52 and port Gi1/0/51.Mar  9 14:52:23.374: %SW_MATM-4-MACFLAP_NOTIF: Host 00cd.fe77.18c7 in vlan 190 is flapping between port Gi1/0/51 and port Gi1/0/52
.Mar  9 14:52:44.673: %SW_MATM-4-MACFLAP_NOTIF: Host 4088.05bf.4a47 in vlan 190 is flapping between port Gi1/0/51 and port Gi1/0/52
.Mar  9 14:52:48.850: %SW_MATM-4-MACFLAP_NOTIF: Host 001e.67d0.5b54 in vlan 72 is flapping between port Gi1/0/52 and port Gi1/0/51
.Mar  9 14:52:52.650: %SW_MATM-4-MACFLAP_NOTIF: Host 00cd.fe77.18c7 in vlan 190 is flapping between port Gi1/0/51 and port Gi1/0/52
.Mar  9 14:53:05.477: %SW_MATM-4-MACFLAP_NOTIF: Host 4088.05bf.4a47 in vlan 190 is flapping between port Gi1/0/51 and port Gi1/0/52
.Mar  9 14:53:22.128: %SW_MATM-4-MACFLAP_NOTIF: Host 00cd.fe77.18c7 in vlan 190 is flapping between port Gi1/0/51 and port Gi1/0/52
.Mar  9 14:53:34.786: %SW_MATM-4-MACFLAP_NOTIF: Host 4088.05bf.4a47 in vlan 190 is flapping between port Gi1/0/51 and port Gi1/0/52
.Mar  9 14:53:46.212: %SW_MATM-4-MACFLAP_NOTIF: Host 6045.bdcc.f4c0 in vlan 76 is flapping between port Gi1/0/51 and port Gi1/0/52

Here is what my Cisco config looks like ...
interface Port-channel2 description EXTREME WIRELESS PORT-CHANNEL
 switchport trunk encapsulation dot1q
 switchport mode trunk
interface GigabitEthernet1/0/51 description EXTREME WIRELESS CONTROLLER LAG2
 switchport trunk encapsulation dot1q
 switchport mode trunk
 channel-group 2 mode on
!
interface GigabitEthernet1/0/52
 description EXTREME WIRELESS CONTROLLER LAG2
 switchport trunk encapsulation dot1q
 switchport mode trunk
 channel-group 2 mode on

From what I am reading, this is usually caused by an etherchannel protocol mis-match. I am assuming that both sides are using LACP. But is that not the case? I can change that on my Cisco side. I have tried on, desireable, and passive. But they all give me the same problem.
switch-serveroomb(config-if)#channel-group 2 mode ?  active     Enable LACP unconditionally
  auto       Enable PAgP only if a PAgP device is detected
  desirable  Enable PAgP unconditionally
  on         Enable Etherchannel only
  passive    Enable LACP only if a LACP device is detected
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Steve Ballantyne

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Posted 2 years ago

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Mel78, CISSP, ECE

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You should have use passive.

mode "on" is neither PAgP or LACP.

Refer to Cisco description below

EtherChannel On Mode

EtherChannel on mode can be used to manually configure an EtherChannel. The on mode forces a port to join an EtherChannel without negotiations. The on mode can be useful if the remote device does not support PAgP or LACP. In the on mode, a usable EtherChannel exists only when the switches at both ends of the link are configured in the on mode.

Ports that are configured in the on mode in the same channel group must have compatible port characteristics, such as speed and duplex. Ports that are not compatible are suspended, even though they are configured in the on mode.

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Steve Ballantyne

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Hello Wong,

Using passive on these two ports gives me the same flapping issue.
interface GigabitEthernet1/0/51 description EXTREME WIRELESS CONTROLLER LAG2
 switchport trunk encapsulation dot1q
 switchport mode trunk
 channel-group 2 mode passive
!
interface GigabitEthernet1/0/52
 description EXTREME WIRELESS CONTROLLER LAG2
 switchport trunk encapsulation dot1q
 switchport mode trunk
 channel-group 2 mode passive
!
switch-serveroomb#term monswitch-serveroomb#
.Mar  9 17:14:40.623: %SW_MATM-4-MACFLAP_NOTIF: Host 6045.bdcc.f4c0 in vlan 76 is flapping between port Gi1/0/51 and port Gi1/0/52
.Mar  9 17:14:50.362: %SW_MATM-4-MACFLAP_NOTIF: Host a866.7fb1.a11c in vlan 190 is flapping between port Gi1/0/51 and port Gi1/0/52
.Mar  9 17:14:52.081: %SW_MATM-4-MACFLAP_NOTIF: Host 3412.98ef.72a0 in vlan 76 is flapping between port Gi1/0/51 and port Gi1/0/52
.Mar  9 17:15:11.526: %SW_MATM-4-MACFLAP_NOTIF: Host 6045.bdcc.f4c0 in vlan 76 is flapping between port Gi1/0/51 and port Gi1/0/52
.Mar  9 17:15:20.343: %SW_MATM-4-MACFLAP_NOTIF: Host a866.7fb1.a11c in vlan 190 is flapping between port Gi1/0/51 and port Gi1/0/52
.Mar  9 17:15:20.963: %SW_MATM-4-MACFLAP_NOTIF: Host 3412.98ef.72a0 in vlan 76 is flapping between port Gi1/0/51 and port Gi1/0/52
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Jeremy, Embassador

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You should set 
   channel-group 2 mode active
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Steve Ballantyne

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Unfortunately, I am still flapping with this setting.
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Jeremy, Embassador

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Steve Ballantyne

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Hello Jeremy, this is what my spanning-tree summary looks like ...

switch-serveroomb#show spanning-tree summary
Switch is in pvst mode
Root bridge for: none
Extended system ID           is enabled
Portfast Default             is disabled
PortFast BPDU Guard Default  is disabled
Portfast BPDU Filter Default is disabled
Loopguard Default            is disabled
EtherChannel misconfig guard is enabled
UplinkFast                   is disabled
BackboneFast                 is disabled
Configured Pathcost method used is short

Name                   Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- -------- ---------- ----------
VLAN0001                     0         0        0         31         31
VLAN0002                     0         0        0         26         26
VLAN0003                     0         0        0         26         26
VLAN0005                     0         0        0         26         26
VLAN0007                     0         0        0         26         26
VLAN0008                     0         0        0         26         26
VLAN0010                     0         0        0         26         26
VLAN0011                     0         0        0         26         26
VLAN0015                     0         0        0         32         32
VLAN0020                     0         0        0         26         26
VLAN0030                     0         0        0         26         26
VLAN0032                     0         0        0         26         26
VLAN0035                     0         0        0         26         26
VLAN0040                     0         0        0         26         26
VLAN0045                     0         0        0         26         26
VLAN0050                     0         0        0         26         26
VLAN0060                     0         0        0         26         26
VLAN0070                     0         0        0         28         28
VLAN0072                     0         0        0         26         26
VLAN0076                     0         0        0         26         26
VLAN0080                     0         0        0         26         26
VLAN0085                     0         0        0         26         26
VLAN0090                     0         0        0         26         26
VLAN0095                     0         0        0         26         26
VLAN0100                     0         0        0         26         26
VLAN0110                     0         0        0         26         26
VLAN0120                     0         0        0         26         26
VLAN0130                     0         0        0         26         26
VLAN0140                     0         0        0         26         26
VLAN0172                     0         0        0         26         26
VLAN0190                     0         0        0         26         26
VLAN0200                     0         0        0         26         26
VLAN0201                     0         0        0         26         26
VLAN0205                     0         0        0         26         26
VLAN0209                     0         0        0         26         26
VLAN0210                     0         0        0         26         26
VLAN0211                     0         0        0         26         26
VLAN0212                     0         0        0         26         26
VLAN0215                     0         0        0         26         26
VLAN0220                     0         0        0         26         26
VLAN0230                     0         0        0         26         26
VLAN0240                     0         0        0         26         26
VLAN0250                     0         0        0         26         26
VLAN0260                     0         0        0         26         26
VLAN0265                     0         0        0         26         26
VLAN0270                     0         0        0         26         26
VLAN0280                     0         0        0         26         26
VLAN0290                     0         0        0         26         26
VLAN0300                     0         0        0         26         26
VLAN0305                     0         0        0         26         26
VLAN0307                     0         0        0         26         26
VLAN0308                     0         0        0         26         26
VLAN0320                     0         0        0         26         26
VLAN0325                     0         0        0         26         26
VLAN0330                     0         0        0         26         26
VLAN0340                     0         0        0         26         26
VLAN0350                     0         0        0         26         26
VLAN0355                     0         0        0         26         26
VLAN0410                     0         0        0         26         26
VLAN0420                     0         0        0         26         26
VLAN0425                     0         0        0         26         26
VLAN0430                     0         0        0         26         26
VLAN0440                     0         0        0         26         26
VLAN0450                     0         0        0         26         26
VLAN0460                     0         0        0         26         26
VLAN0462                     0         0        0         26         26
VLAN0463                     0         0        0         26         26
VLAN0465                     0         0        0         26         26
VLAN0470                     0         0        0         28         28
VLAN0475                     0         0        0         26         26
VLAN0480                     0         0        0         26         26
VLAN0483                     0         0        0         26         26
VLAN0485                     0         0        0         26         26
VLAN0490                     0         0        0         31         31
VLAN0493                     0         0        0         26         26
VLAN0495                     0         0        0         26         26
VLAN0510                     0         0        0         26         26
VLAN0520                     0         0        0         26         26
VLAN0525                     0         0        0         26         26
VLAN0550                     0         0        0         26         26
VLAN0560                     0         0        0         26         26
VLAN0570                     0         0        0         26         26
VLAN0625                     0         0        0         26         26
VLAN0630                     0         0        0         27         27
VLAN0650                     0         0        0         26         26
VLAN0661                     0         0        0         26         26
VLAN0666                     0         0        0         33         33
VLAN0700                     0         0        0         26         26
VLAN0720                     0         0        0         26         26
VLAN0730                     0         0        0         26         26
VLAN0740                     0         0        0         26         26
VLAN0745                     0         0        0         26         26
VLAN0760                     0         0        0         26         26
VLAN0777                     0         0        0         26         26
VLAN0800                     0         0        0         26         26
VLAN0900                     0         0        0         27         27
VLAN0950                     0         0        0         26         26
VLAN0975                     0         0        0         26         26
VLAN0999                     0         0        0         26         26
VLAN1000                     0         0        0         26         26
---------------------- -------- --------- -------- ---------- ----------
100 vlans                    0         0        0       2629       2629
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Steve Ballantyne

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GTAC got me straightened out. I think I was running into a wall trying to change through the various settings without downing the ports in the process. GTAC tells me that the correct mode for the channel-group is "on". The Wireless LAG ports do *NOT* use LACP, and so this needed to be configured as a "static lag".

Here is that article.

And here is the config that worked!

interface Port-channel2 switchport trunk encapsulation dot1q
 switchport mode trunk
!
interface GigabitEthernet1/0/51
 description EXTREME WIRELESS CONTROLLER LAG2
 switchport trunk encapsulation dot1q
 switchport mode trunk
 channel-group 2 mode on
!
interface GigabitEthernet1/0/52
 description EXTREME WIRELESS CONTROLLER LAG2
 switchport trunk encapsulation dot1q
 switchport mode trunk
 channel-group 2 mode on
!
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Jeremy, Embassador

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Ohh yes, that is true!  So you wouldn't be able to use a control protocol.   I was thinking of the LACP issues I had between our S4 and a Cisco 6509..