Configuring GigaEthernet interface on CSS 11503

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Mar 6th, 2007
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I am trying to configure a coonection between a CSS 11503 and a 3750 switch via a fiber to RJ45 converter and got problem to get connectivity. By the way i am also having the same issue to set up my ISC link between my two CSSs (both are CSS 11503). I have disabled the Auto negotiation, i am getting the link but no ip connectivity. Both interface (ISC port and interface 2/2) are up, the vlan 1 associtated to my port 2/2 is also up and ip enabled but i am not getting any ip connectivity. Can someone help?


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Syed Iftekhar Ahmed Tue, 03/06/2007 - 11:21
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My first suggestion would be to hardcode port settings on both CSS and switch. Compare the two using "show phy" on CSS and "Sh interface" on Switch

try this


interface 2/1

phy 1Gbits-FD-no-pause

On switch

interface GigabitEthernet 1/1

speed 1000

flowcontrol send off

flowcontrol recieve off

Hope it helps

Syed Iftekhar Ahmed

naslamenace Wed, 03/07/2007 - 08:06
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Thank you, i'll try that but any idea for the ISC link between my two CSSs, should i also disable the auto-neg and set both interfaces to phy 1Gbits-FD-no-pause?

By the way my switch is a 3750 and only support the command flowcontrol receive off. Is still the solution ok or should I use another phy option (for instance sym-asym).



Syed Iftekhar Ahmed Wed, 03/07/2007 - 10:20
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Try removing Phy command from ISC interfaces

To remove phy command from config, use following

command from interface mode of gig interface

css(config-if[1/1])#phy 1Gbits-FD-sym-asym

I hope you are not using any Layer 2 device to connect ISC ports of two CSSs.You must connect ISC ports directly.

Syed Iftekhar Ahmed

naslamenace Wed, 03/07/2007 - 12:32
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Actually there is no layer two device but a fiber to RJ45 converter and I am wondering if this can be an issue or not. So one side is connected via a LC fiber and the reomte CSS is connected via RJ45 to a converter.

Should that work. Actually even my 3750 is connected via an RJ45 port to the converter which then connect my CSS via a fiber.

Do you think the config will still work, I will try it tomorrow at the customer premises so any idea would be appreciated.



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