Possibly a bad cable ?
Cisco commands-
speed 1000
duplex full
to set back to auto
speed auto
duplex auto
Cisco commands-
speed 1000
duplex full
the bigiron wants (iirc):
spe 1000-full
i strongly suggest you peruse the cli reference for both devices.
-p
Hi,
To: "Randy Bush" <randy@psg.com>; "David Hubbard" <dhubbard@dino.hostasaurus.com>
Cc: "Sam Stickland" <sam_ml@spacething.org>; <nanog@nanog.org>
Sent: Sunday, January 15, 2006 4:45 PM
Subject: RE: Problems connectivity GE on Foundry BigIron to Cisco 2950TCisco commands-
speed 1000
duplex fullthe bigiron wants (iirc):
spe 1000-full
i strongly suggest you peruse the cli reference for both devices.
On the foundry GBIC blades you can't configure the speed and duplex settings, they only support 1000-full.
(config-if-e1000-1/2)#speed-duplex 1000-full
Error - can't change speed and duplex mode
I've dug through as much information as I can about the cisco 2950T and 802.3z/802.3ab and disabling the auto-negiation. There appears to be no command at all available to do this.
The cabling arrangement is:
Foundry -- Straight -- Patch -- Underfloor -- Patch -- Crossover -- Cisco
GBIC Cable Panel Straight Panel Cable
If I replace the final crossover cable with a straight, change the foundry to a 10/100 port, and plug the final end into a host NIC instead of the cisco I get a connection. Crossover cable has been changed twice now, and the RJ45 GBIC was previously working in a cisco 6500.
I am extensively familar (at least I believe I am) with both these models, and this one has me stumped.
If nobody else can see any configuration errors I guess I'm down to hardware issues.
Sam
Replying to my own email..
I've found some sites that suggest it's not possible to disable auto-negotiation on 1000Base-T since other operational parameters are negotiated including selection of the master clock signal. I was aware that flow control was negotiated, but not the clock signal.
Can anyone elaborate?
Sam
Sam Stickland wrote:
Replying to my own email..
I've found some sites that suggest it's not possible to disable auto-negotiation on 1000Base-T since other operational parameters are negotiated including selection of the master clock signal. I was aware that flow control was negotiated, but not the clock signal.
Can anyone elaborate?
Sam
Hi,
To: "Randy Bush" <randy@psg.com>; "David Hubbard" <dhubbard@dino.hostasaurus.com>
Cc: "Sam Stickland" <sam_ml@spacething.org>; <nanog@nanog.org>
Sent: Sunday, January 15, 2006 4:45 PM
Subject: RE: Problems connectivity GE on Foundry BigIron to Cisco 2950TCisco commands-
speed 1000
duplex fullthe bigiron wants (iirc):
spe 1000-full
i strongly suggest you peruse the cli reference for both devices.
On the foundry GBIC blades you can't configure the speed and duplex settings, they only support 1000-full.
(config-if-e1000-1/2)#speed-duplex 1000-full
Error - can't change speed and duplex modeI've dug through as much information as I can about the cisco 2950T and 802.3z/802.3ab and disabling the auto-negiation. There appears to be no command at all available to do this.
The cabling arrangement is:
Foundry -- Straight -- Patch -- Underfloor -- Patch -- Crossover -- Cisco
GBIC Cable Panel Straight Panel CableIf I replace the final crossover cable with a straight, change the foundry to a 10/100 port, and plug the final end into a host NIC instead of the cisco I get a connection. Crossover cable has been changed twice now, and the RJ45 GBIC was previously working in a cisco 6500.
I am extensively familar (at least I believe I am) with both these models, and this one has me stumped.
If nobody else can see any configuration errors I guess I'm down to hardware issues.
Sam
Cisco Infrastructure Port Recommendation
Configuring auto-negotiation is much more critical in a GE environment than in a 10/100 environment. In fact, auto-negotiation should only be disabled on switch ports that attach to devices not capable of supporting negotiation, or where connectivity issues arise from interoperability issues. Cisco recommends that Gigabit negotiation be enabled (default) on all switch-to-switch links and generally all GE devices. The default value on Gigabit interfaces it auto-negotiation, but is still a good general practice to issue the following command to insure that auto-negotiation is enabled:
switch(config)#interface <type> <slot/port>
switch(config-If)#no speed
!--- Sets the port to auto-negotiate Gigabit parameters.
I have not looked at the RFC in a while but I thought when it first came out that auto negotiation had to be used on GigE.
Hi,
<snip>
The cabling arrangement is:
Foundry -- Straight -- Patch -- Underfloor -- Patch -- Crossover -- Cisco
GBIC Cable Panel Straight Panel CableIf I replace the final crossover cable with a straight,
Just do that ^^^ and give it a try.
802.3ab claims that you can't disable autonegotiation on 1000Base-T, but lots of vendors allow you to anyway.
In 100 and 10Base-T, autonegotiation decides speed, phy type and duplex. In 1000Base-T, you add in a master/slave clock source negotiation. If autonegotiation is working, the master/slave thing just 'works'. If autonegotiation is disabled and your gear allows you to force 1000mbps, you also need to manually set which is the master and which is the slave. If you do nothing, most PC/server NICs force themselves into "slave" mode, and most switches force themselves into "master" mode. For the most part, this is correct and will result in it working fine. If it isn't, you have to hope your gear supports being able to toggle it. For example, in the BSD drivers for some Broadcomm and SysKonnect cards, setting the "link0" flag on the device will flip it. For Intel chips, there's a define in the driver source.
Personally, I'd look at the copper GBIC first. Many vendors have had trouble with supporting them, and have been the cause for problems for me in the past. Make sure the version of the OS on your device claims to actually support copper GBICs.
Will do.
If that fails I might have to dig out a non-passive 1000SX to 1000-BaseT media convertor that's on one of the other sites and give that a try.
Btw, several people have suggested "speed nonegotiate" on the cisco speed. This command is only supported on GBIC slots on cisco, not on fixed 1000Base-T interfaces (at least not a Sup720/WS-X6748-GE-TX).
I also found this reference about the clock signals in use on 1000Base-T:
"Synchronous transmission
1000BASE-T is based on synchronous transmission to facilitate the cancelation of Echo/NEXT/FEXT interferences at the receivers. To achieve synchronous transmission between the two PHYs at the ends of a link, a master-slave clocking relationship is established by the PHYs. The master-slave relationship between two stations sharing a link segment is established during auto-negotiation. The master PHY uses an external clock to determine the timing of transmitter and receiver operations. This master clock is also provided to the other stations in the network. The slave PHY recovers the clock from the received signal and uses it to determine the timing of transmitter operations. In a typical network, the PHY at the repeater will become the master and the PHY at the data terminal equipment (DTE) will become the slave."
So it would appear that auto-negotiation is a requirement in 1000Base-T.
Sam
Having done a bit more looking into this myself, one thing that might be
a cause is the cross-over, in the sense that if it is a 100BASE-T
crossover, only two of the pairs will be crossed, and the other two
pairs are usually wired straight.
A GigE cross over, assuming you need one if you're ports don't support
automatic cross over, has all four pairs crossed over
(1-3,2-6,3-1,6-2,4-7,5-8,7-4,8-5). My guess would be that if a device
only detects two of the four pairs crossed, it drops back to 100BASE-T.
In other words, GigE cross overs are backwards compatible with
10/100BASE-T, but 10/100BASE-T crossovers aren't forward compatible with
GigE.
A GigE rated straight through path would be the first thing I'd test,
after that, possibly try a GigE crossover somewhere between the devices.
Regards,
Mark.
Wikipedia reveals all. http://en.wikipedia.org/wiki/Crossover_cable
Turns out that for 1000Base-T crossovers pairs 2 and 3, and 1 and 4 have to swapped. Standard TIA-568B to TIA-568A over swaps 2 and 3.
Auto MDI/MDI-X is optional in the 1000Base-T spec so the way forward is to try a straight cable and if that fails I'll have to make up a 1000Base-T crossover cable.
Thanks for all the help people,
S
Thanks Mark - just found the same thing out myself 
S