so, i wish i had done my homework a little bit more before buying the 71605H. in my search regarding this hanging at boot time during warm boot or dropping of drives, i ran into several postings online with similar issues. I'm posting this here for the benefit of anyone else who might come along searching for this information:
1) first, back in 2013, someone encountered a similar hang of the 71605H with pm80xx (version 0.1.37) driver in kernel 3.10 (which is the kernel for CentOS 7, coincidentally):
The pm80xx driver hangs in 3.10 with the Adaptec 71605H HBA (Linux SCSI)
that thread eventually lead to a patch:
[SCSI] pm80xx: fix Adaptec 71605H hang · linux-pmfs/pmfs@9504a92 · GitHub
which is great, but I haven't been able to figure out if Red Hat back ported this patch to their 3.10 kernel. the kernel RPM changelog has no mention of it that i can tell.
2) in 2014, there was a report of the 71605H randomly dropping drives:
Fwd: Adaptec 71605H HBA randomly failing to detect any drives at init (Linux SCSI)
the conclusion was not encouraging, basically the person switched to LSI controller and gave up on the 71605H:
Re: Adaptec 71605H HBA randomly failing to detect any drives at init (Linux SCSI)
3) similar report around the same year on Ubuntu 12.04.4, which has kernel 3.11 i believe, so not sure if the above patch was applied at this point or not:
Adaptec pm80xx Driver Drops Drives Randomly
4) the review of this card on newegg makes an interesting remark:
Adaptec Series 7H Family 71605H PCI-Express 3.0 x8 MD2-Low Profile SATA / SAS Host Bus Adapter (HBA) - Newegg.ca
I quote it here in case it disappears:
Great HBA with caveats5/29/2016 3:01:43 PM
Pros: SAS/SATA support, up to 12 drives
Works out of the box with current Fedora, Ubuntu, Debian, Arch Linux, Red Hat , and more
Cons: A fan(not included) is absolutely necessary to keep the card functioning properly and at optimal temps.
Other Thoughts: Make sure to update the BIOS from the adaptec website, this card running the old firmware was pretty buggy. No issues whatsoever after the update.
I've got mine running a BTRFS RAID-6 array like a champ. Forget using a RAID card, HBA all the way!
which happens to coincide with some of the problem reports about drives randomly disappearing or not reliably booting when there's more than 12 drives connected, which is exactly my case (i had 16 drives connected).
So, the symptoms are:
- the native Linux pm80xx driver (version 0.1.37) hangs during reboot when there are more than 12(?) drives connected (for sure 16)
- when it eventually does finish booting, only 14 of the 16 drives are detected (this is exactly what i experienced)
BTW, for CentOS 7.4 and 3.10.x kernel, the Adaptec driver source code does not compile. Also, their binary RPM will not install either, even though they claim it is for CentOS 7, perhaps 7.0 or 7.1, but does not work on 7.4.
My Fedora 26 workstation has a newer version of the pm80xx driver at 0.1.38 with kernel 4.14.6. So, I might try to install Fedora 26 with the 71605H and see if the newer driver resolves the problem. If so, it would suggest that the patch #1 above didn't get back ported to RHEL7 kernel, in which case I might open a bugzilla ticket about it or download the kernel source package to confirm the driver doesn't have that patch... that's my next step.