[email protected] (Tinker), 2016.02.20 (Sat) 21:05 (CET): > So glad to understand better what's in the box. > > Also please note that I'm not trying to suggest to implement lots of > crap, am perfectly clear that high security is correlated with low > complexity. > > On 2016-02-21 00:29, Marcus MERIGHI wrote: > >[email protected] (Tinker), 2016.02.20 (Sat) 16:43 (CET): > .. > >You appear to mean bioctl(8). Thats the only place I could find the word > >'patrol'. bioctl(8) can control more than softraid(4) devices. > > > >bio(4): > > The following device drivers register with bio for volume > > management: > > > > ami(4) American Megatrends Inc. MegaRAID > > PATA/SATA/SCSI RAID controller > > arc(4) Areca Technology Corporation SAS/SATA RAID > > controller > > cac(4) Compaq Smart Array 2/3/4 SCSI RAID controller > > ciss(4) Compaq Smart Array SAS/SATA/SCSI RAID > > controller > > ips(4) IBM SATA/SCSI ServeRAID controller > > mfi(4) LSI Logic & Dell MegaRAID SAS RAID controller > > mpi(4) LSI Logic Fusion-MPT Message Passing Interface > > mpii(4) LSI Logic Fusion-MPT Message Passing Interface > > II > > softraid(4) Software RAID > > > >It is talking about controlling a HW raid controller, in that 'patrol' > >paragraph, isn't it? > > So by this you mean that patrolling is really implemented for > softraid??
No, I said the opposite. I'm sure my english language capabilities are not perfect. But what you make of it is really surprising! (And even funny in the cabaret way.) I'll keep trying. But sooner or later we'll have to take this off list. Or to newbies. There you get help from the same people but without having your misinterpretations in the 'official' archives for other poor souls to find ;-) http://mailman.theapt.org/listinfo/openbsd-newbies > (Karel and Constantine don't agree??) > > So I just do.. "bioctl -t start sdX" wher sdX is the name of my softraid > device, and it'll do the "scrub" as in reading through all underlying bioctl(8) is clear, I think: -t patrol-function Control the RAID card's patrol functionality, if supported. patrol-function may be one of: Why do you think it will work for softraid(4) when it says it does for hardware-RAID? I have a theory: you have some experience with other Operating Systems and their built in help system that have led you to not fully read but just search/skim for keywords. Do yourself (and me) a favour and read them fully. Top to bottom. Take every word as put there thoughtfully, not in a hurry. You can find manpage content discussions all over the archives. manpages are taken seriously. Please repeat: bio(4)/bioctl(8) controls RAID devices. These can be in hardware or software. Some functions (-a, -b, -H, -t, -u) are only useable/usefull when controlling a hardware RAID. The manpage even gives direct clues on whether hardware- or software RAID is the topic. First synopsis, second synopsis. 'The options for RAID controllers are as follows:' (=hardware) 'In addition to the relevant options listed above, the options for softraid(4) devices are as follows:' (=software). Did you note the 'relevant' part? That word is there on purpose, I suppose. It is there to tell you that not all, but the relevant parts of the hardware RAID parameters also apply to software RAID (that comes below). I would consider '-v' relevant, '-a' ('Control the RAID card's alarm functionality, if supported') not. (Example: what '-a' does for hardware RAID can be done with sensorsd(8) for software RAID (=softraid(4)). Once a softraid volume is configured, you get 'hw.sensors.softraid0.drive0=online (sd1), OK'. Try 'sysctl hw.sensors.softraid0'.) > physical media to check its internal integrity so for RAID1C that will be > data readability and that checksums are correct, and "doas bioctl softraid0" > will show me the % status, and if I don't get any errors before it goes back > to normal it means the patrol was successful right? No idea, never had a hardware RAID controller. > (And as usual patrol is implemented to have the lowest priority, so it > should not interfere extreemely much with ordinary SSD softraid operation.) I think the patrolling is done by the hardware RAID controller. bioctl(8) just commands it to do so. > >> * Rebuild - I think I saw some console dump of the status of a rebuild > >>process on the net, so MAYBE or NO..? > > > >That's what it looks like: > > > >$ doas bioctl softraid0 > >Volume Status Size Device > >softraid0 0 Rebuild 12002360033280 sd6 RAID5 35% done > > 0 Rebuild 4000786726912 0:0.0 noencl <sd2a> > > 1 Online 4000786726912 0:1.0 noencl <sd3a> > > 2 Online 4000786726912 0:2.0 noencl <sd4a> > > 3 Online 4000786726912 0:3.0 noencl <sd5a> > > Yey!! > > Wait, can you explain to me what I would write instead of "device" and > "channel:target[.lun]" in "bioctl -R device" and "bioctl -R > channel:target[.lun]", AND what effect those would have? The above rebuild was started with: $ bioctl -R /dev/sd2a sd6 ^^^=RAID volume ^^^^^^^^^=replacement chunk Sidenote: In fact it was started as 'bioctl -R /dev/sd3a sd7'; I did a reboot in between, ordering of the disk devices changed but the rebuild continued flawlessly. > Say that my sd0 and sd1 SSD:s run a RAID1C already, can I then make softraid On a 'OpenBSD 5.9 (GENERIC.MP) #1870: Mon Feb 8 17:34:23 MST 2016', from snapshots, bioctl(8) says: Valid raidlevels are: 0 RAID 0: A striping discipline. 1 RAID 1: A mirroring discipline. 5 RAID 5: A striping discipline with floating parity chunk. C CRYPTO: An encrypting discipline. c CONCAT: A concatenating discipline. What is that 'RAID1C' thing your keep talking about? > extend my RAID1C with my sd2 SSD by "rebuilding" it, as a way to live-copy > in all my data to sd2, so this would work as a kind of live attach even if > expensive? If your sd0 or sd1 fails you can replace them in hardware with sd2 or have sd2 already plugged and start a rebuild as shown above. There are no bioctl(8) parameters for modifying an existing volume. Just for rebuilding (-R) and failing (-O). > Does it work for a softraid that's live already? A softraid(4) disk is 'just another disk'(tm). Nothing special. You can growfs(8) and tunefs(8), I suppose. And you can restore from backups after you had to do bigger changes than can be done with these utilities. No parameters that indicate 'modifiy' or 'edit' or 'append'. Just that '-l' to list the chunks for creating a volume. I'd suggest just playing with it. If you have no real disks for that, take a look at vnconfig(8) and vnd(4); use two of these as chunks for a softraid volume. Warning: I have not tested this (vnd+softraid). Then try to extend, append, enlarge, shrink, whatever. > >> * Hotspare - MAYBE, "man softraid" says "Currently there is no > >>automated > >>mechanism to recover from failed disks.", but that is not so specific > >>wording, and I think I read a hint somewhere that there is hotspare > >>functionality. > > > >bioctl(8) > > -H channel:target[.lun] > > If the device at channel:target[.lun] is currently marked > > ``Unused'', promote it to being a ``Hot Spare''. > > > >That's the only mention of 'hot spare'. And again talking about > >controlling a hardware RAID controller, isn't it? > > > >What is 'not so specific' about 'no' (as in "Currently there is *no* > >automated mechanism to recover from failed disks")? > > Awesome. > > I guess "bioctl softraid0" will list which hotspares there are currently, > and that "-d" will drop a hotspare. There are no hot spares as seen from bioctl(8). You, the operator, know that disk sdXYZ is a hot spare, sitting there plugged but idle. Then, when one of your chunks fails, you do bioctl -R sdXYZa sdABC. sdXYZa = your "hot spare": just a disk that is already connected to the system but not used sdABC = your softraid volume (your RAID1C, what ever that is) > The fact that there is hotspare functionality, How come you think so? > means that there are cases when softraid will take a disk out of use. I do not get the connection from a wrong assumption to the above statement but: Yes, there are cases when softraid will take a disk out of use. It looks somewhat like this: $ doas bioctl softraid0 Volume Status Size Device softraid0 0 Degraded 12002360033280 sd6 RAID5 0 Offline 4000786726912 0:0.0 1 Online 4000786726912 0:1.0 noencl <sd3a> 2 Online 4000786726912 0:2.0 noencl <sd4a> 3 Online 4000786726912 0:3.0 noencl <sd5a> > That will be when that disk reports itself as COMPLETELY out of use ALL BY > ITSELF, such as self-detaching itself on the level of the SATA controller or > reporting failure via some SMART command? The reasons why *my* softraid RAID5 went degraded is not clear to me but it is documented on bugs@. A block could not be read, kernel panic. Reboot, rebuild, ... > A disk just half-breaking with broken sectors and 99% IO slowdown will not > cause it to go offline though so I guess I should buy enterprise drives with > IO access time guarantees then. Listen to nick@ (Nick Holland). Search for his older posts, too! Are you, for instance, sure your motherboard and all other parts in the way can handle a disk that just spins down and disconnects from the SATA/whatever bus? Or are you going to have to deal with a kernel panic anyways? > >> * Hotswap - MAYBE, this would depend on if there's rebuild. Only > >>disconnect > >>("bioctl -O" I think; "bioctl -d" is to.. unmount or self-destruct a > >>softraid?) > > > >bioctl -O should fail the chunk specified, simulating hardware failure. > >After this command you have an 'Offline' chunk in the 'bioctl' output. > > > >bioctl -d 'detach', not 'destroy'; just as sdX appears when you assamble > > a softraid volume, this makes it go away. better unmount before... > > So "-d" is to take down a whole softraid. "-O" could work to take out a > single physical disk but it's unclean. Please get used to - and use the terms: -d takes the *volume* down. -O fails a *chunk*. > So then, there is a very unrefined hotswapping functionality in that "-O" > can be used to take out a single physical drive, and "-R" (if I understood > it correctly above) can be used to plug in a drive. You are using unusual terms ('take out a single physical drive' vs. 'Set the state of device or channel:target[.lun] to offline') but basically '-O' => offline, '-R' => rebuild => online. > Preferable would be to "hotswap" the whole softraid by simply taking it > offline altogether ("bioctl -d [raid dev]") and then taking it online ^^^^^^^^^^ = volume > altogether ("bioctl -c 1 -l [comma-separated devs] softraid0") ^^^^ = chunks What has happened after taking it offline and bringing it back up? Have you swapped chunks? Broken one taken out, good replacement shoved in? How is bio(4) supposed to know? What I think should happen: - you have a RAID1 volume sd3 - assembled from the chunks sd1a and sd2a - you notice 'something is wrong' e.g. clicking sounds coming from sd2 - you do 'bioctl -0 sd2a sd3' or, if your hardware allows, just pull out sd2. - you replace the failed chunk: either you have a 'hot spare' already plugged in and waiting; or if your hardware allows, you just shove it in; or, as in my case, you shut the system down, replace the disk and restart. - In case of reboot your RAID1 volume comes up degraded. In all other cases it just stays degraded. In any case you pray your remaining disk keeps working. - the replacement disk shows up as sd4 (for whatever reason, maybe you left the failed one connected) - you do all the setup for the new disk (see softraid(4) -> EXAMPLES) - you do 'bioctl -R sd4a sd3', rebuild starts. > >>The man pages are sometimes over-minimalistic with respect to an > >>individual > >>user who's trying to learn, this is why I'm asking for your > >>clarification. > > > >I am quite sure the man pages are kept as condensed as they are on > >purpose. > > > >You can always read mplayer(1) if you want something lengthy ;-) > > > >>So your clarifications would still be much appreciated. > > > >Nothing authoritative from me! > >I am just trying to flatten your learning curve. > Awesome. Thank you so much! It's taken me over an hour on a rainy sunday to answer; please use at least the same amount of time on investigating before answering. Bye, Marcus
