01-22-2010 12:18 AM - edited 03-06-2019 09:24 AM
Hi,
I have the following issue;
I am getting a duplex mismatch between a Cisco 2960 TT-L Switch running IOS 12.2(35) LAN Base Image (Gig0/1) and a Cisco 6506 Switch running IOS 12.2(33)SXH Adv IP Services (Gig2/19).
I have tried several combinations of the duplex/speed settings on both sides but the only that works is setting duplex/speed AUTO on the Cisco 2960 which ends up autonegotiating to HALF duplex and 100Mbps.
What cou;d be the issue? IOS bugs?
Regards,
Edd.
01-22-2010 01:33 AM
is it using UTP cable ?
please try to replace with another cable.
01-22-2010 01:38 AM
Hi,
I have upgraded the Cisco 2960 Switch to version 12.2(52). The interfaces are now at FULL duplex but cannot negotiate to 1000Mbps.
01-22-2010 04:42 AM
Hi,
Can you put here results of sh run int ... commands?
thnx
01-22-2010 04:57 AM
Hi,
Ports are on default;
2960
-------
int gig0/1
switchport mode access
switchport access vlan zzz
duplex auto
speed auto
6500
--------
int gig2/18
no switchport
ip address x.x.x.x y.y.y.y
no speed
no duplex
01-22-2010 05:36 AM
Hi,
Is there only cable between those 2 boxes, or is there some convertor (fiber optic)?
Also you can try speed nonegotiate command on both sides.
bye
01-22-2010 05:55 AM
i am pretty sure i saw a similar bug.
Varun
01-22-2010 09:35 PM
On both, try the following interface command "speed auto 1000".
01-23-2010 04:56 AM
It is generally advised you use auto on both sides for gigabit. If they are not negotiating gig then I would take a serious look at the cabling . Unlike fastether which takes 2 pairs you must have 8 good wires in the entire path between the 2 devices in order to negotiate gig as gig uses all 8 wires to achieve gig speeds . Even 1 bad wire out of the 8 it will not negotiate gig . Make sure speed negotation is actually turned on for the 6500. you can check this with the following counterintuitive command no speed nonegotiate . Verify with the command
Good info for explaining the different states for gig port settings. http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/ios/12.2SX/configuration/guide/intrface.html#wp1020621show interfaces GigabitEthernet slot/port transceiver properties
06-28-2012 03:20 PM
On the 2960 switch the "dual purpose" uplinks need to be manually configured with "media-type" to be able to set speed/duplex. Default would not allow setting these 2 attributes.
interface GigabitEthernet0/1
switchport mode trunk
media-type rj45
speed 100
duplex full
end
GigabitEthernet0/1 is down, line protocol is down (notconnect)
Hardware is Gigabit Ethernet, address is
Description: Uplink to Cat01
MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not set
Full-duplex, 100Mb/s, link type is auto, media type is 10/100/1000BaseTX
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