On Fri, 04 May 2012 10:48:36 +0000, Ramon Hofer wrote: > On Thu, 03 May 2012 20:27:02 +0000, Camaleón wrote:
>> There's some useful information in one of the links I sent before: >> >> http://wiki.debian.org/LinuxRaidForAdmins > > Maybe I miss something but the page doesn't say anything about cli tools > of the megaraid cards :-? Yes... no info is also info after all. Not the one you'd like to read but that's how it is :-). Anyway, the page can be simply outdated or lacking from that specific information. Also, the expanded information on the "megaraid_sas" driver points to the page you sent before: http://hwraid.le-vert.net/wiki/DebianPackages Where you can find a set of tools for your driver ("megaclisas-status" and "megacli") as well as more information about the LSI controllers and the driver status: http://hwraid.le-vert.net/wiki/LSIMegaRAIDSAS Ufff, I was not aware of this: *** There is currently no known opensource tool for theses cards. *** How, how bad... in contrast, 3ware seems to fully support open source, or at least that's what it can be read here: http://hwraid.le-vert.net/wiki/3Ware *** 3Ware supports Linux and provide an opensource kernel driver which has been part of Linux for ages *** This is something to reconsider. >> In case of disasterous raid failure you depend completely on the >> manufacturer and what are the option they can provide (although data >> recovery can be usually done at professional labs). > > My data isn't so important that it would justify restoring it with > professional help. > > Still I have to do backups of the really important stuff to dvd or a > seperate external drive... Yes, and very good point. A RAID system can never substitute the backups, they have to be set in paralel (RAID cares about hardware issues while backups about software/logical/user errors). >> Just an additional note. By reading the chosen card specs it seems it >> does not support a RAID 6 level (which is better than RAID 5 because it >> allows the failure 2 disks) so that can be a handycap. > > This should be no problem. I plan to use four slots without raid for > mythtv. > I already have a 4x 1.5 TB disks raid 5 and another 4x 2 TB disks raid > 5. When I want to add more disks I can e.g. go for 3 TB disks and set 4 > of them up as another raid5. > Like this I can use disks with different sizes. Just a note of caution here. RAID 5 with big hard disks can be a real pain and a real problem. If one of the arrays go down, the rebuilding operation can take up to "days" (depending on the controller's capacity) and if while the RAID is rebuilding a second disk of the array is also down for whatever reason (it can be a false possitive) you can't recover your data, at least not that easily. That's why most people is switching from raid 5 to raid 6, it adds an extra of security with no remarkable drawbacks. > I'm thinking of combining the arrays then to a lvm... But I don't know > if this is a good idea as it adds more complexity :-? Yes, it will be a good idea (it will allow you to manage your volumes in a more flexible manner) and yes, it will add an extra layer of complexity (RAID+LVM) :-) Greetings, -- Camaleón -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/jo0t52$3du$9...@dough.gmane.org
