I have a 6-bay fibre channel disk array that--unlike the rest of my SAN setup--doesn't take 15 minutes to fire up. So it's been extremely useful for quick and easy I/O testing.
This particular model has been discontinued for a while and it only supports 1 and 2 Gbps link speeds. I recently got a batch of brand new drives that support 4 Gbps operation. And unfortunately the array backplane turned out to be incapable of negotiating link speeds with them.
First I tried to download a manual. I filled out the web form and waited for the "guaranteed next business day response"... Nothing.
Then I contacted the vendor's tech support who has been fantastic at getting back to me in the past. This time: No response. Neither from the web form, nor via email. I know this is a discontinued product, but still...
I worked around the problem by powering up the array with an old 1 Gbps drive plugged in. Once things settled down I hotplugged the 4 Gbps drives which happily went to 1 Gbps link speed. I never got the same stunt working with a 2 Gbps "bootstrap" drive. So I had to live with 1 Gbps.
But the main downside to this workaround was that I had to be in the lab every time I needed the array. Thus defeating the quick and easy criteria that was my main reason for using it in the first place.
Yesterday, I stumbled upon a manual for the array. I used the amazing powers of jumper W5 to force backplane to speed 2 Gbps. And presto! It worked.
I should point out that when I initially got the 4 Gbps disks I had tried several jumper combinations in an attempt to force link speed. But between backplane and I/O daughterboard there are many combinations.
All I really needed from the vendor's tech support was two letters: "W5". Was that really too much to ask? And why on earth don't they just put their manuals up for download?
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