100M Copper on an SFP Port?

[Methius]

Greetings

Our regional CLEC has been using the Alcatel Omniswitch family (replacing Cisco ME3400's) for a year and a half now, and I've never looked back. We currently have about 10 6850's, 10 6400's and maybe 75 6250's in the field. There is one thing that's been bugging me about these switches, and I'm wondering if there is a solution to it.

On the Cisco gear, it's possible to hard-set an SFP port to 100M with a Copper based SFP and have it talk to a FastEthernet port on the other end.

With NO SFP installed, I get the following:
-> interfaces 2/21 speed auto
ERROR: Fiber GigaEthernet port accepts 100/1000

With Copper SFP part # GLC-T installed, I get the following:
-> interfaces 1/21 speed 100
ERROR: Fiber GigaEthernet with gig SFP accepts only 1000

Any thoughts? Am I using the wrong part # transceiver?

Thanks in advance

[slixxboy]

for the combo ports of the OS6850 or OS6400, do this command:
-> interfaces 1/1-4 hybrid copper autoneg disable
-> interfaces 1/1-4 hybrid copper speed 100
-> interfaces 1/1-4 hybrid copper duplex full

[Methius]

Right, this is on an SFP port, not a hybrid port.

[jlettinck]

Looking in the Transceivers guide the following is stated:

SFP-GIG-T
Gigabit SFP Copper Transceiver.
Connector Type RJ-45
Standards Supported 802.3z, SFP MSA
Connections supported 1000Base-T
Cable Type CAT5, CAT5e, CAT6
Transmission Distance ∼100 m
Digital Diagnostic Monitoring Not Supported


This would suggest that the tranceiver is not capable of 100M connections.

For example, there are dual-speed transceivers. The transceivers guide states the following on these:

SFP-DUAL-MM
Dual-Speed SFP Optical Transceiver.
Connector Type LC
Standards Supported 802.3z, 802.3ah, SFP MSA
Connections Supported 100Base-FX, 1000Base-LX
Fiber Type MMF
Wavelength 1310 nm
Average Power Output 100Base-FX: -20 to -14 dBm
1000Base-LX: -11.5 to -3 dBm
Receiver Sensitivity 100Base-FX: -28 dBm
1000Base-LX: -22 dBm
Transmission Distance 550 m at 1000 Mbps
2 km at 100 Mbps
Operating Temperature 0 ºC to 70 ºC
Digital Diagnostic Monitoring Not Supported

However, Alcatel-Lucent does not have dual-speed Copper transceivers that I am aware of.

[devnull]

It depends.

I had the problem with OEM Copper SFPs which only support 1000T, but Alcatel Certified Copper SFPs are active, so they support 10/100/1000.
And have a look on the Transceiver Guide
OS6850:
SFP-GIG-T Not Supported in ComboPorts Supported since 6.1.3 (in U24X)

So in U24X you may be lucky, in Combo Ports you won't (but you have the copper Ports anyway..
Will not work in the 10G SFP Ports though..

And you need the right SFPs not the Cheap compatible ones

[helyousa]

Hello, i'm getting the same problem with a SFP RJ45 100/1000Base-T on 6850 with firmware 6.4.4. Is there any fix ? May be upgrading the firmware ?

[silvio]

6.4.4 is the latest release for 6850 (without "E"). So the info is still the same:
1. Release 6.3.1.R02 added support for the SFP-GIG-T at 10/100/1000 Mbits on OS6850-U24X noncombo ports only.
2. SFP-GIG-T is not supported on OS6850 combo ports.

regards
Silvio

[helyousa]

Thank you for answering but i'm getting this problem with 6.4.4 which is superior to 6.3.1 and it's not on an combo port.

[silvio]

Than you have an 6850-U24X. At ports 1-24 the Alcatel SFP-GIG-T should work. But in my knowledge this supports only 1000BaseT.
But it will be difficult for you to get any more support: the switch is out of support than a lot of years....
regards
Silvio

[helyousa]

Yes i have a 6850-U24X and with your experience, you're saying that you don't see them working at 100M?
Do you know if i plug a SFP RJ45 100Mbit directly on it, will it work ? not a 100/1000 but just a 100Mbps