01-17-2003 11:48 AM - edited 03-02-2019 04:17 AM
I am having trouble trunking these two switches together. I am running a Here is the following information that I am seeing:
I have a foundry router trunking to the gig port on a 3548. I am announcing the 10.5.0.1/29 off of the virtual interface 7. I have set the mgnt vlan (int vlan 7 )10.5.0.2/29, and can ping across to gateway...but I can't get the 3548 to trunk with the 2950 (10.5.0.3)? I don't know if looking at the sh int * switchport is telling me something or not. On the 3548, I see the following "Access Mode VLAN: 0 ((Inactive))", and on the 2950 I see this, "Access Mode VLAN: 1 (default)." I keep getting incomplete arp entries, and can't ping across. I have tried to the "switchport nonegotiate" on the 2950 as well, and this didn't change anything. I have changed both switches native vlan from 1 to 1000, and have moved the mgnt vlan from 1 and 7 as well.Then I tried to trunk two 2950s...same config on both and no luck, until I enable the "switchport nonegotiate" command on both switch ports. Any ideas of what I may be doing wrong.
gig3-3548#sh arp
Protocol Address Age (min) Hardware Addr Type Interface
Internet 10.5.0.3 0 Incomplete ARPA
Internet 10.5.0.2 - 0007.8502.c740 ARPA VLAN7
Internet 10.5.0.1 95 0004.8048.7500 ARPA VLAN7
interface FastEthernet0/1
duplex full
speed 100
switchport trunk encapsulation dot1q
switchport mode trunk
no cdp enable
!
gig3-3548#sh int fa0/1 switchport
Name: Fa0/1
Switchport: Enabled
Administrative mode: trunk
Operational Mode: trunk
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: dot1q
Negotiation of Trunking: Disabled
Access Mode VLAN: 0 ((Inactive))
Trunking Native Mode VLAN: 1 (VLAN1)
Trunking VLANs Enabled: ALL
Trunking VLANs Active: 1,7,1000
Pruning VLANs Enabled: 2-1001
Priority for untagged frames: 0
Override vlan tag priority: FALSE
Voice VLAN: none
Appliance trust: none
gig3-3548#sh vlan
VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
1 default active Fa0/2, Fa0/3, Fa0/4, Fa0/5,
Fa0/6, Fa0/7, Fa0/8, Fa0/9,
Fa0/10, Fa0/11, Fa0/12, Fa0/13,
Fa0/14, Fa0/15, Fa0/16, Fa0/17,
Fa0/18, Fa0/19, Fa0/20, Fa0/21,
Fa0/22, Fa0/23, Fa0/24, Fa0/25,
Fa0/26, Fa0/27, Fa0/28, Fa0/29,
Fa0/30, Fa0/31, Fa0/32, Fa0/33,
Fa0/34, Fa0/35, Fa0/36, Fa0/37,
Fa0/38, Fa0/39, Fa0/40, Fa0/41,
Fa0/42, Fa0/43, Fa0/44, Fa0/45,
Fa0/46, Fa0/47, Fa0/48, Gi0/2
7 VLAN0007 active
1000 VLAN1000 active
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------
1 enet 100001 1500 - - - - - 1002 1003
7 enet 100007 1500 - - - - - 0 0
1000 enet 101000 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 1 1003
1003 tr 101003 1500 1005 0 - - srb 1 1002
1004 fdnet 101004 1500 - - 1 ibm - 0 0
1005 trnet 101005 1500 - - 1 ibm - 0 0
interface FastEthernet0/1
description gig-3548
switchport mode trunk
no ip address
duplex full
speed 100
no cdp enable
agg5-2950#sh int fa0/1 switchport
Name: Fa0/1
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: trunk
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: dot1q
Negotiation of Trunking: On
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Trunking VLANs Enabled: ALL
Pruning VLANs Enabled: 2-1001
Protected: false
Voice VLAN: none (Inactive)
Appliance trust: none
agg5-2950#sh vlan
VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
1 default active Fa0/2, Fa0/3, Fa0/4, Fa0/5
Fa0/6, Fa0/7, Fa0/8, Fa0/9
Fa0/10, Fa0/11, Fa0/12, Fa0/13
Fa0/14, Fa0/15, Fa0/16, Fa0/17
Fa0/18, Fa0/19, Fa0/20, Fa0/21
Fa0/22, Fa0/23, Fa0/24
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------
1 enet 100001 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
TIA,
D-
01-20-2003 01:42 AM
Hi,
your problem description is not 100% clear, but I would do following:
1) move mgmt VLAN back to VLAN1 on both switches, enable CDP
2) enable trunk negotiation on both ends (now it's diabled on 3550 and enabled on 2950)
3) check if trunk has come up correctly (Trunking VLANs Active: should list the same VLAN numbers on both trunk sides).
If not: CDP should detect different native VLANs and display an error message to syslog. If trunk negotiation would'n work correctly, I'd try to disable it - but on BOTH line ends).
4) When the trunk is OK then try to move mgmt VLAN to VLAN7 (if it's really necessary, I wouldn't recommend it generally). Finally, disable CDP if you want it disabled.
Regards,
Milan
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