Allied Telesyn MC101XL vs Catalyst 2948G 1

[ruswahyudi]

Hi there,

I have a problem while trying to connect Allied Telesyn MC101XL to Catalyst 2948G.

Note:
MC101XL is Fiber Optic to Ethernet converter (which is cheper then CISCO GBIC).

Instead of buying expensive CISCO GBIC, I'd like to combine the MC101XL solution with Catalyst. My objective is to bring trunk over the fiber optic.

Unfortunately, the trunk seems cannot be delivered over the MC101XL. Does anybody out there have similar experience & the solution?

Is it possible to combine MC101XL and Catalyst to avoid expensive GBIC?

Regards,
Ruswahyudi

 

[vipergg]

The fiber optic converter should have no effect whether or not the two will trunk , this sounds like more of a config issue . If you don't want to use a Cisco you can gbics that are a "lot" cheaper than cisco's own brand . You have to check to see if your Allied Telesyn will run 802.1Q trunking protocol . I know the 2948 will trunk using 802.1Q . Try setting both units to trunk unconditionally or on .

 

[BuckWeet]

I say go the GBIC way, cleaner, and the 2948G's have gig ports on them, whereas that allied telesyn is only 100MB..

Anything external, I'm usually against.. for the lack of its something else to fail, something else to plug-in, etc...

BuckWeet

 

[ruswahyudi]

Vipergg, I did test my configuration on both switches by put ethernet cross cable between the two. I can bring the trunk succesfully through the ethernet cross cable.

But, when I simply change the connection from cross-cable to FO converter to Ethernet. All things go wrong. I do not have an idea until today.


Buckweet, you are obviously right. But I didn't have the options .

Regards,
Ruswahyudi

 

[vipergg]

Look for an MDI/MDI-X switch on the fiber optic converter , this switch will let you use crossover or straight thru . Possible this switch is set wrong . We have run into this in soemn of our fiber installs .

 

[ruswahyudi]

Thanks Vipergg,

I just indentified that we use different type of Allied Telesyn Converter. At my end, I use MC101XL - but in the other end they use AT-FS202.

I am not quite sure about this, but I am going to try to use similar type in my end, and see what happens.

Thanks for your suggestion anyway.

Rgds,
Ruswahyudi

 

[kite1212]

Hello Ruswahyudi,

we have the exact dame problem as you have. This has nothing to do with trunk encap, crossover or not etc etc. There must be an other explaination to this problem.

I was wondering if you saw the light yet...Please let me know if you have.....


Greetz Marc Erkens

 

[robertjo24]

Try forcing the switch ports connected to the Allied Telesyn converters to 100Mbit / Full Duplex.
We had some problems getting the Cisco switches to auto dtect various fiber converters/unmanaged(cheap) switches in the past.
Let me know if this helps.

 

[kite1212]

Ok did a little research. The problem is in the way the transceivers work. With the link test off the link to the other end of the connection will not come up without user interferance. The user has to apply the link switch on the transceiver to get the link up. Every time something happens with the fiber or rj45 link the link will not come up again when the link test is off. If you want the link to come up automaticaly the have to enable the link test on the tranceivers. You can read this infoermation on the allied telesyn site.

Greetz MArc

 

[ruswahyudi]

Marc, thanks for your help.

I found this problems several weeks ago while I was visiting remote site. I cannot do any research there because time is so critical. I just simply ignore the fiber optic & use existing backup telephone cable.

I will try your suggestion in my next visit. I will let you know whether I succesful or not.

Cheers,
Ruswahyudi

 

[kite1212]

Ok just came out of our lab. What i found is somewhat disturbing. First there are to types of MC101XL transceivers.
A: Without the Autonegotiate switch. With this one i found the following;
It does not matter how the linktest switch is positioned.Link test on or off works. That is the link will come up automaticaly. When the fiber link is down the switchport will follow, and thats ok if you want spanning tree to do its job. No user action is needed to get the link up again.
B: MC101XL With the Autonegotiate switch. With this one i found the following; tested with cisco 2950G (12.1.14.EA1) and 3500XL 12.0.5(WC8)
When link test is off, thus m/l is on, in case of link failure (fiber or UTP) the link will not be automaticaly restored. You have to press the link test button in order to get the link up again. Now you can put the link test on in order to get your link automaticaly up again. But theres the catch. If your fiber link or the RJ45 link at the remote end will fail, your cisco switch F0/xx interface and line protocol will stay up, and spanning tree will NOT go to the backup link. This mains that your site is down dispite op redundancy.When i use de G0/x port on the 2950G the story is somewhat different. When a linkfailure on the remote end (3500) occurs and the M/L option is on, the link will comeup again. The interface will follow the Fiber and RJ status at the romete end. There seems to be a difference between Fastethernet en Gigabitethernet ports. Now this is what i do not understand. The Gigabit interface configured on 100Mb Full duplex works fine with the M/L switch on. Fastethernet does not work with the M/L switch on and user interferance is needed.

Anybody ??

Greets Marc