Siwtching

[tmkte]

hello in my institute we have CISCO CATALYST 4506 and 2960x switches when i try to connect those devise 4506 to 2960x using straight through UTP cable with trunk interface  both devises didn't connect ,cant see any link status LED blink ,i think some how the physical link not connected via utp cable. what can be the problem and solutions

[Mark Malone]

Is this a straight copper connection between both devices ?

can you provide the configuration from both sides and the show interface of each interface when connected and the show int trunk command

[tmkte]

is their any possibility to make interface in catalyst 4506 as trunk without dot1q encapsulation

[Mark Malone]

No you need dot1q as its the trunking protocol or ISL but that's legacy now , dot1q is the open standard trunk protocol most vendors use

[Joseph W. Doherty]

Technically, yes, if your two switches support another trunking encapsulation, such as Cisco's earlier ISL.  But, as Mark also noted, that's legacy and current standards use dot1q.

[tmkte]

it is straight copper utp  with catalyst c2960 24tt l and catalyst 4506 no problem work finely problem ,problem accord when we try to connect 2960 X and 4506

[Mark Malone]

Ok well if you post some config we should be able to help further but we need to see whats happening at cli level

sh int trunk .... off both switches

show int gx/x .. for the trunk ports interfaces effected  both sides 

show run int gx/x...for the trunk ports interfaces effected  both sides

this to start with to see what's happening at the interface level

[Joseph W. Doherty]

Switch port to switch port, you need either a cross-over cable, or at least one side that supports auto-MDI.

Many later Cisco switch support auto-MDI, but not if you disable auto negotiate.

[tmkte]

you mean if we disable auto negotiate in both devise we have to connect via cross over cable

[Mark Malone]

I think what Joseph means  is some older switches cannot convert from straight through to a crossover without a feature called MDIX which should be available on your 2960 but maybe not on the 4506 but you could try it , like for like devices must use crossover between them if MDIX is not supported , here is how you set it up below if not enabled by default

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst2960x/software/15-0_2_EX/int_hw_components/configuration_guide/b_int_152ex_2960-x_cg/b_int_152ex_2960-x_cg_chapter_011.html

Example for Configuring Auto-MDIX

This example shows how to enable auto-MDIX on a port:

		Switch# configure terminal
		Switch(config)# interface gigabitethernet1/0/1
		Switch(config-if)# speed auto
		Switch(config-if)# duplex auto
		Switch(config-if)# mdix auto
		Switch(config-if)# end
		

Auto-MDIX on an Interface

When automatic medium-dependent interface crossover (auto-MDIX) is enabled on an interface, the interface automatically detects the required cable connection type (straight through or crossover) and configures the connection appropriately. When connecting switches without the auto-MDIX feature, you must use straight-through cables to connect to devices such as servers, workstations, or routers and crossover cables to connect to other switches or repeaters. With auto-MDIX enabled, you can use either type of cable to connect to other devices, and the interface automatically corrects for any incorrect cabling. For more information about cabling requirements, see the hardware installation guide.

This table shows the link states that result from auto-MDIX settings and correct and incorrect cabling.

[Joseph W. Doherty]

Yup, if neither switch support auto-MDI/MDIX, then switch to switch, you need a cross-over cable.