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Media Converter Problem


I have about 10 2924 switch’s and two cat 4006 box’s I have also set up 10 Vlans that each switch is dedicated to, all the switch’s are connected physically back to a WS-x4124FX switching module in the 4006 and they are all trunked using dot1q. My problem is that in one area where there is no switch I want to use a Hub/media Converter (Magnum DS80F) that is also connected back to the switching mod. I can’t get it to work.

I switched the port on the switching mod to the vlan I want the Hub in. What else do I need to do ?


Re: Media Converter Problem

Check the following on the port on the 4124-FX:

A1. If your switchport mode is trunk, then set your native VLAN to be the one you want the hub in.

A2. If your switchport mode is access, double-check that the VLAN specified is the one you want. Also, make sure there is not a switchport mode trunk command active on the port. (That is, if you have switchport access vlan xx and switchport mode trunk commands on the same port, trunking will be in effect.)

B. In either case, make sure duplex is set to full. Fast Ethernet fiber ports do not auto-detect duplex. Maximum segment length of multimode fiber between the switch port and the fiber port on your DS80F is 2000 meters in full-duplex, and only 412 meters in half-duplex. (Full is always better, unless you are connecting a true hub.)

Check the following on the fiber port of the DS80F:

C. Manual switch F-H is set to F, to force the fiber port to operate in full-duplex mode at 100Mbps. (Garrett com documentation indicates that 1SW copper and 2SW fiber ports are switched, the rest are shared or hub ports.)

Check your fiber:

D. If you're not seeing link lights at either end, you may have TX going to TX, and RX going to RX. On one patch cable connection, swap the connectors so that you get TX going into RX, and RX going into TX.

E. If you're still not seeing link, use a known good patch cable to plug the DS80F directly into the 4124-FX. (This helps you figure out whether you have a bad patch cable, or maybe a problem with the longer horizontal/vertical fiber run.)

Hope this helps.