canyoufixit Posted November 23, 2009 Posted November 23, 2009 Hi, Can anyone help me with a probelm i have with a fibre link. A few months ago we had a fibre link installed to get networking over to an isolated building. The company installed the fibre cable, terminated at patch panels and supplied two switches. We then bought some fibre patch cables and connected them up but the link doesn't appear to be active. The company has since gone into liquidation so our only option is to try and figure it out or get our council IT Support to it at a cost. Obviously i would rather not have the extra cost so any help would be much appreciated. We've never really had to do anything with Fibre connections so i'm not sure if it should just work by connecting it or if something needs setting up in the menus. Info Four Core fibre cable (about 100m) 2 x HP Procurve 2610 switches with sx mini gbics installed. Multinode 50/125 dublex lc-sc fibre patch cables. The switches show the mini gbics as being installed and enabled but there is no activity. Thanks in advance for any help. Ben
localzuk Posted November 23, 2009 Posted November 23, 2009 Are the fibres the same as the patch leads? ie. are the cables 50/125?
Ric_ Posted November 23, 2009 Posted November 23, 2009 If you unplug the patch cables and place a piece of paper by the GBIC, can you see a red light flashing? Oh and... a stupid question... you did patch the same pairs of fibres at either end? 1
Michael Posted November 23, 2009 Posted November 23, 2009 With most (if not all HPs) you can only use one of the dual ports, either Fibre or Ethernet not both. There are usually two sets of dual ports. One dual pair could be using Ethernet and the other dual pair Fibre. Hope this makes sense 1
canyoufixit Posted November 23, 2009 Author Posted November 23, 2009 Ahhh i meant to ask about that in the original post. I'm not sure what the main fibre link is. If the main link is 62.5/125 and the patch cables are 50/125 will it not work?
localzuk Posted November 23, 2009 Posted November 23, 2009 Ahhh i meant to ask about that in the original post. I'm not sure what the main fibre link is. If the main link is 62.5/125 and the patch cables are 50/125 will it not work? Nope, they have to be the same type of fibre all the way from transceiver to transceiver.
canyoufixit Posted November 23, 2009 Author Posted November 23, 2009 Does fibre cable have the type written on the actual cable? so i can check if it's 50/125 or 62.5/125. I'll try moving the mini gbic to the other port as i am using the ethernet port above it. Although i'm sure i read in the manual that they are independant. Thanks for all your suggestions
canyoufixit Posted November 23, 2009 Author Posted November 23, 2009 ok cool, i will check later when i get chance, It's over the other end of the school.
plexer Posted November 23, 2009 Posted November 23, 2009 I think in the 2610 switches you can use all dual personality ports. Cross over one end.
DMcCoy Posted November 23, 2009 Posted November 23, 2009 Once all the patch cables and fibre are the correct size, you will often have to switch one of the pairs on the cable as if they are both the same then both will try to send/receive on the same fibre. Fibre patch leads are often individual connectors, or the LC ones will usually have a little clip holding the pair together so you can swap them over. 1
canyoufixit Posted November 23, 2009 Author Posted November 23, 2009 Update Managed to go over and try a few things. Checked the cables and they are both 50/125. Opened up the patch panel to check the same cores are going to the same place and they are. Moved the mini gbic to the other available slot just in case. made no difference. removed the patch cable and put paper in front of it. Couldn't see any flashing lights.
localzuk Posted November 23, 2009 Posted November 23, 2009 Update Managed to go over and try a few things. Checked the cables and they are both 50/125. Opened up the patch panel to check the same cores are going to the same place and they are. Moved the mini gbic to the other available slot just in case. made no difference. removed the patch cable and put paper in front of it. Couldn't see any flashing lights. When you have the GBICs in place in the switchs, is there light coming from them? (ie. removing the fibre from the equation). If they do, plug in a patch lead to each and see, does the light pass through each of them? If it does, makes me think 'dead fibre'. 1
canyoufixit Posted November 23, 2009 Author Posted November 23, 2009 Thanks for all your help everyone. Saved the school a few hundred pounds! It turned out DMcCoy was right and i needed to swap over the connectors on one of the patch cables. Sprang to life after that.
Michael Posted November 23, 2009 Posted November 23, 2009 Glad you got it sorted. Amazing what can happen when you get a load of brains together on here
maniac Posted November 23, 2009 Posted November 23, 2009 For future reference when troubleshooting fibre problems, I often find two people each with a radio or mobile phone and a little torch useful. You can shine it down each fibre in turn, and have the person at the other end look for the corresponding light coming from the patch panel. Quick and dirty test to make sure there's no breaks in the fibre. Also if the patch leads are different to the installed fibre (i.e if one is 50/125 and one 62.5/125) then they will still work, but you will get lots of data transmission errors. I had some connections cabled up like this for ages becuase we couldn't get hold of the correct patch leads, and the performance was fine, just the switch reported errors every so often. Mike.
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