01-22-2008 06:50 PM - last edited on 03-05-2019 08:38 PM by NikolaIvanov
Trunk and EtherChannel were united between Catalyst6509(CatOS) and
Catalyst2950.
EthetChannel was not able to be united ahead normally when turning on
power after it blacked out.
The composition and LOG are the following.
Are not there any hints?
---Physical connection---
CAT2950-FA0/23 <-> CAT6509-3/27
CAT2950-FA0/24 <-> CAT6509-4/27
---Config---
Cat6509 + Sup2
clear trunk 3/27 3-6,8-1001,1025-4094
set trunk 3/27 desirable dot1q 1-2,7,1002-1005
set port channel 3/27 mode desirable silent
clear trunk 4/27 3-6,8-1001,1025-4094
set trunk 4/27 desirable dot1q 1-2,7,1002-1005
set port channel 4/27 mode desirable silent
Cat2950
!
interface FastEthernet0/23
switchport trunk allowed vlan 1,2,7,1002-1005
switchport mode trunk
channel-group 1 mode desirable
!
interface FastEthernet0/24
switchport trunk allowed vlan 1,2,7,1002-1005
switchport mode trunk
channel-group 1 mode desirable
!
---LOG---
Cat2950
%EC-5-DONTBNDL: Fa0/24 suspended: incompatible partner port with FastEthernet0/23
%EC-5-DONTBNDL: Fa0/24 suspended: incompatible partner port with FastEthernet0/23
Cat6509
%DTP-5-NONTRUNKPORTON:Port 4/27 has become non-trunk
%DTP-5-TRUNKPORTON:Port 4/27 has become dot1q trunk
%DTP-5-NONTRUNKPORTON:Port 4/27 has become non-trunk
%DTP-5-TRUNKPORTON:Port 4/27 has become dot1q trunk
---PORT STATUS---
Cat6509
4/27 connected trunk a-full a-100 10/100BaseTX
Cat2950
Fa0/24 notconnect trunk a-full a-100 10/100BaseTX
Solved! Go to Solution.
01-23-2008 05:04 PM
I believe Edison is correct , on the catos side when you do the ports individually it will put them in different port channel groups and won't be able to agregate them which is indicated by your debug . Group them together and they should build the channel and trunk just fine . We haven't had any problems autonegotiating trunks or etherchannels on catos boxes.
01-22-2008 07:32 PM
On the CatOS side type:
set port channel 3/27,4/27
On the 2950 side type:
interface range f0/23-24
shut
no shut
HTH,
__
Edison.
01-22-2008 08:08 PM
thank you.
The setting has already been done.
Besides, though there might be a cause ・・・
set port channel 3/27,4/27 28
01-22-2008 07:37 PM
Hi
I think u are missing with cmd for trunking method to be used at 2950.
Use the cmd "switchport trunk encapsulation dot1q" on ports fa0/23 and fa0/24..
Also i dont thing the Pgap need to configure on silent mode.Silent mode is used when the other end is not capable of Pgap.
arun
01-22-2008 07:40 PM
Arun,
2950 does not support ISL hence the only option is 802.1q
When there is only one option, the encapsulation command is not available.
I believe the problem is with the CatOS not having 3/27 and 4/27 as channel partners. The command I recommended should fix the issue.
__
Edison.
01-22-2008 07:44 PM
Thanks edison for correcting me... :)
arun
01-22-2008 08:27 PM
I tried the below.
ï½¥The Trunk mode is changed from Dynamic to turning on and it connects it. (2950 was
connected with LAN cable between 6509 again. )
ï½¥Restart of 2950
Debug was made effective by 2950 and the information gathering was
done.
debug dtp event
debug pagp event
debug dtp packet
The result is appended LOG.
Is anything understood?
I am doubting that PAGP is doubtful.
01-22-2008 08:41 PM
1) Can you change the trunk on the 6509 from desirable to on ?
2) Can you change the channel-group on the 2950 from desirable to auto ?
Do step 1 first, if it doesn't work then do step 2.
__
Edison.
01-23-2008 04:34 PM
Thank you for advice.
I will try on weekend.
It reports on the result again.
01-23-2008 05:04 PM
I believe Edison is correct , on the catos side when you do the ports individually it will put them in different port channel groups and won't be able to agregate them which is indicated by your debug . Group them together and they should build the channel and trunk just fine . We haven't had any problems autonegotiating trunks or etherchannels on catos boxes.
01-28-2008 01:04 AM
The setting change was done getting a hint from advice.
When the channel setting of 6509 and 2950 was made ON Mode, it became
normal.
Thank you.
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