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Cannot get a new Catalyst 3850 switch to link to our existing Catalyst 3750G switch

Hello - we have an existing network stack of Cisco Catalyst 3750 switches, and just installed a new stack of 3850 switches, which we need to link together through Ethernet ports on the front of each.  the new 3850 stack has been assigned an IP address on the same subnet as the 3750s, but I'm not able to ping back and forth, or see any resources on the network from the 3850s.  What are some things to check?

Thanks
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Damian_Gardner
Asked:
Damian_Gardner
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1 Solution
 
Damian_GardnerAuthor Commented:
here are log files of the CONFIG and RUN for both the old 3750 and the new 3850 switches.
3750.txt
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Damian_GardnerAuthor Commented:
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djcanterCommented:
all the ports on the 3750 stack are configured for:

 switchport access vlan 2

 switchport mode access

the 3850 all the ports are In native vlan1.

run the following to put 1/0/1 in vlan 2 on the 3850
 
config t
interface GigabitEthernet1/0/1
switchport mode access
switchport access vlan 2
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Damian_GardnerAuthor Commented:
Hi - thanks for your help.  so after I execute this command, I would need to connect the 3850 by it's 1st port, correct?
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djcanterCommented:
correct. Any other ports on the 3850 that need to be in vlan 2 will also need to be configured with the same commands.
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Damian_GardnerAuthor Commented:
ok - I executed the commands, and plugged into what I thought was 1/0/1, but here's what it tells me:

*Aug 11 12:38:47.735: %LINK-3-UPDOWN: Interface GigabitEthernet2/0/1, changed st
ate to up
*Aug 11 12:38:48.737: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEth
ernet2/0/1, changed state to up
Switch(config-if)#
*Aug 11 12:39:17.734: %LINK-3-UPDOWN: Interface Vlan1, changed state to up
*Aug 11 12:39:18.734: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, cha
nged state to up


SO THIS LOOKS LIKE PORT 2/0/1 ON THE STACKED SWITCH. IF I PULL IT AND PLUG INTO THE THE OTHER PORT #1:

Switch(config-if)#
*Aug 11 12:43:52.325: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEth
ernet2/0/1, changed state to down
*Aug 11 12:43:53.324: %LINK-3-UPDOWN: Interface Vlan1, changed state to down
*Aug 11 12:43:53.325: %LINK-3-UPDOWN: Interface GigabitEthernet2/0/1, changed st
ate to down
*Aug 11 12:43:54.325: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, cha
nged state to down
*Aug 11 12:43:56.389: %CDP-4-NATIVE_VLAN_MISMATCH: Native VLAN mismatch discover
ed on GigabitEthernet1/0/1 (2), with lacocoresw.laco.internal GigabitEthernet1/0
/1 (1).
*Aug 11 12:43:56.485: %LINK-3-UPDOWN: Interface GigabitEthernet1/0/1, changed st
ate to up
*Aug 11 12:43:57.395: %CDP-4-NATIVE_VLAN_MISMATCH: Native VLAN mismatch discover
ed on GigabitEthernet1/0/1 (2), with lacocoresw.laco.internal GigabitEthernet1/0
/1 (1).
*Aug 11 12:43:57.484: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEth
ernet1/0/1, changed state to up
*Aug 11 12:43:58.401: %CDP-4-NATIVE_VLAN_MISMATCH: Native VLAN mismatch discover
ed on GigabitEthernet1/0/1 (2), with lacocoresw.laco.internal GigabitEthernet1/0
/1 (1).
Aug 11 12:44:26.485: %LINK-3-UPDOWN: Interface Vlan2, changed state to up
*Aug 11 12:44:27.485: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan2, cha
nged state to up
*Aug 11 12:44:58.407: %CDP-4-NATIVE_VLAN_MISMATCH: Native VLAN mismatch discover
ed on GigabitEthernet1/0/1 (2), with lacocoresw.laco.internal GigabitEthernet1/0
/1 (1).
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Damian_GardnerAuthor Commented:
it's pinging now, actually.  I just didn't know what to think about the "vlan mismatch"
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Damian_GardnerAuthor Commented:
I can telnet into the new switch stack now, so I think I might be ok.  What are thoughts on the mismatch message?

thanks
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Damian_GardnerAuthor Commented:
well...I think there's still a problem. even though I can ping and telnet into the new switch, when I re-route my desktop client machine from the old 3750 into the new 3850 switch, it fails to find the network and does not get an IP address.  This must be caused by the vlan mismatch, I think...
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djcanterCommented:
can you post a show run from the 3850 again please/
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Damian_GardnerAuthor Commented:
I ended up calling Cisco - they were able to figure it out.  not sure what they did, but had something to do with the mismatched vlans on the 2 ports.

thanks for your help.
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