> On Nov 11, 2020, at 8:04 PM, John Pierce <jhn.pierce at gmail.com> wrote: > > in large raids, I label my disks with the last 4 or 6 digits of the drive > serial number (or for SAS disks, the WWN). this is visible via smartctl, > and I record it with the zpool documentation I keep on each server > (typically a text file on a cloud drive). I get info about software RAID failure from cronjob executing raid-check (coming with mdadm rpm). I can get S/N of failed drive (they are not dead-dead, still one query one) using smartctl, but I am too lazy to have all serial numbers of drives printed and affixed to fronts of drive trays… but so far I see no other way ;-( Valeri > zpools don't actually care > WHAT slot a given pool member is in, you can shut the box down, shuffle all > the disks, boot back up and find them all and put them back in the pool. > > the physical error reports that proceed a drive failure should list the > drive identification beyond just the /dev/sdX kind of thing, which is > subject to change if you add more SAS devices. > > I once researched what it would take to implement the drive failure lights > on the typical brand name server/storage chassis, there's a command for > manipulating SES devices such as those lights, the catch is figuring out > the mapping between the drives and lights, its not always evident, so would > require trial and error. > > > > On Wed, Nov 11, 2020 at 5:37 PM Valeri Galtsev <galtsev at kicp.uchicago.edu> > wrote: > >> >> >>> On Nov 11, 2020, at 6:00 PM, John Pierce <jhn.pierce at gmail.com> wrote: >>> >>> On Wed, Nov 11, 2020 at 3:38 PM Warren Young <warren at etr-usa.com> wrote: >>> >>>> On Nov 11, 2020, at 2:01 PM, hw <hw at gc-24.de> wrote: >>>>> >>>>> I have yet to see software RAID that doesn't kill the performance. >>>> >>>> When was the last time you tried it? >>>> >>>> Why would you expect that a modern 8-core Intel CPU would impede I/O in >>>> any measureable way as compared to the outdated single-core 32-bit RISC >> CPU >>>> typically found on hardware RAID cards? These are the same CPUs, mind, >>>> that regularly crunch through TLS 1.3 on line-rate fiber Ethernet >> links, a >>>> much tougher task than mediating spinning disk I/O. >>> >>> >>> the only 'advantage' hardware raid has is write-back caching. >> >> Just for my information: how do you map failed software RAID drive to >> physical port of, say, SAS-attached enclosure. I’d love to hot replace >> failed drives in software RAIDs, have over hundred physical drives attached >> to a machine. Do not criticize, this is box installed by someone else, I >> have “inherited” it.To replace I have to query drive serial number, power >> off the machine and pulling drives one at a time read the labels... >> >> With hardware RAID that is not an issue, I always know which physical port >> failed drive is in. And I can tell controller to “indicate” specific drive >> (it blinks respective port LED). Always hot replacing drives in hardware >> RAIDs, no one ever knows it has been done. And I’d love to deal same way >> with drives in software RAIDs. >> >> Thanks for advises in advance. And my apologies for “stealing the thread" >> >> Valeri >> >>> with ZFS you can get much the same performance boost out of a small fast >>> SSD used as a ZIL / SLOG. >>> >>> -- >>> -john r pierce >>> recycling used bits in santa cruz >>> _______________________________________________ >>> CentOS mailing list >>> CentOS at centos.org >>> https://lists.centos.org/mailman/listinfo/centos >> >> _______________________________________________ >> CentOS mailing list >> CentOS at centos.org >> https://lists.centos.org/mailman/listinfo/centos >> > > > -- > -john r pierce > recycling used bits in santa cruz > _______________________________________________ > CentOS mailing list > CentOS at centos.org > https://lists.centos.org/mailman/listinfo/centos