Thunderbolt Pegasus R4 Experience?

I have just bought a Pegasus 2 R4 as a Media drive for my iMac. It has Western Digital HDDs and so far I have nothing but praise for its performance. However when I attempted to daisy chain a backup drive using the Thunderbolt to Firewire 800 adaptor, the second drive didn't show up. After reading this excellent thread I realised that which Thunderbolt port I was using made a difference. With the iMac connected to the Left port and the Firewire adaptor in the Right port it now functions as expected.

Wouldn't you think that something as obvious as this should be in the User Guide?

So I just spent all night reading all these posts. Still working through things and trying out a ton of new stuff. Here is my current situation-

Have ran my R6 Pegasus for about a year and a half with no problems what so ever. The thing has been clean, connected to an IMac late 2012. I swear just this week though the thing won't stay connected to my Mac. I have tried different Cables, position of system, Firmware was updated to current already but did another install of the same firmware, I have tried every firewire port combination there is. I have not done a Tin foul in the firewire but I am tryign that now by just circumventing any and all other wires in the system.

Last disconnect was 30 minutes ago and seems to be holding well since I have rerouted the cable, but I am very pessimistic right now. - Wondering if the new mac updates I installed fouled things up?

I have a Promise Pegasus R4. One of the hard drives failed and I replaced it. I followed the instructions to rebuild it using the Promise Utility. Now all of the check marks are green but I still can't write to the drive. I've tried to use the OS Disk Utility but that doesn't work. Advice welcome!

Thanks!

amy

This solution fixed my problem and with a previous Imac had the same problem a couple of years ago and this was the solution that fixed it as well .

Thanks

What a disaster.

Since launching Sierra 10.2 my Mac will not communicate with my Pegasus 2 R4. I have spent 2 days on the phone with Apple support, which is a bit of a lottery, some good people some, not so much (The line times out and you do not get to speak to the same person twice). They concluded the problem was with my Pegasus 2 R4. I contacted my supplier RENTARAID Neil was as helpful as he could be, but eventually directed me to the 'Promise support centre'. The first time I tried I was advised, curtly, to phone USA (from Scotland). Eventually I found my way through the "support centre" website and found an e-mail address in Holland. Joris, our supporter, went through all the things that we had already been through and concluded, again after two days, that our two and a half year old device was broken and that we should buy another one. Guess what! That is not going to happen. We thought we were buying the best but it seems we have bought the worst. This was to be our failsafe device. - What a waste of £940.95!