Marc SCHAEFER wrote: > on a Debian bullseye uptodate system [1], I experiment frequent (every > 3-4 hours on heavy load) disk disconnections from a md RAID10 array with > 4 drives connected to an USB 10000M adapter [2]. > > Errors do not look like a timeout, but like a DMA error [3]. > > Immediately after, the disk reappears as a new drive name and can be > re-added quickly to the md RAID array (I am doing those tests with a > read-only mounted filesystem for obvious reasons). > > Initially, I was wondering if it was maybe a disk doing a too long > recovery procedure, but it is to be noted that it's not always the same > disk which has an error, and smartctl -a shows no recorded errors for > any of the 4 drives [4]. The drives are connected to a SATA-to-USB > enclosure [6]. > > This is on a 3.1 USB PCI-Express card [5]. > > I already applied this work-around (which does not seem to apply to a > non-idle system): > echo -1 > /sys/module/usbcore/parameters/autosuspend > > What would be your recommandations? I have thought about downgrading to > a slower port (it should not be much different with 5000M), changing the > cable, or maybe it's the enclosure?
I have never had long-term happiness with multiple disks connected via USB. I strongly recommend that you find a 4 or 8 disk SATA/SAS PCIe card -- an LSI 2008, for example -- and connect through that, instead. US prices are $40-45 new. Add $15 for an 8087-to-4xSATA cable, you will have happiness for less than $75. -dsr-
