Re: md (software) RAID missing in the installer for sparc
On Wed, Apr 04, 2007 at 08:26:12PM +0200, Josip Rodin wrote: [ Fabio M. Di Nitto ] * RAID cannot be selected if we are on sparc AND the partiton starts at 0 otherwise there will partition table corruption happening in the first 512 bytes of the disk. I found another bit of info, from Fabio: https://launchpad.net/ubuntu/+source/silo/+bug/66727/comments/2 (Upon further meddling with my setup, I managed to make my system unbootable again, so I'm still investigating :) I wasn't able to reproduce the working condition with a 3.5 GB root (/) md0 partition, or a 2 GB root md0. :( I've finally created a 256 MB /boot md0, and a 5 GB root (/) md1 partition, and finally PROM found SILO. Someone who knows PROM and/or SILO could explain which of those variables causes the boot process to fail. -- 2. That which causes joy or happiness. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: md (software) RAID missing in the installer for sparc
On Tue, 17 Apr 2007, Josip Rodin wrote: I wasn't able to reproduce the working condition with a 3.5 GB root (/) md0 partition, or a 2 GB root md0. :( I've finally created a 256 MB /boot md0, and a 5 GB root (/) md1 partition, and finally PROM found SILO. Someone who knows PROM and/or SILO could explain which of those variables causes the boot process to fail. There are several factors involved. 1) The OBP does not understand raid, but it should be able to cope with a simple mirror. 2) Older OBPs cannot see beyond either 1Gb or 2Gb into a partition depending on version. If your installer puts anything needed for the initial boot process beyond this point you will not be able to boot. [ Affects Sparc32 ] 3) The first cylinder of the disk contains the partition information. Most filesystems work around this by not actually using the first cylinder, but Linux Raid does not understand this and it will overwrite the tables. The solution is simple - just create a small partition of one cylinder at cylinder zero and do not use it. [ Affects Linux Raid and possibly oddball filesystems such as XFS only when they start at cylinder zero ] 4) If the partition table on the disk was first written by an old version of the Solaris format command the maximum useable size of any partition will be either 1Gb or 2Gb depending on version. Linux will probably not notice and allow you to create a larger partition which will confuse the OBP even if the OBP does not have the limitation in 2) above. The workaround for this is to destroy cylinder zero by filling it with zeros using dd and then use Linux fdisk to create a new BSD table. [ Affects disks initially formatted with old utilities ] You could have any combination of the above - best to avoid them all. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: md (software) RAID missing in the installer for sparc
On Tue, Apr 17, 2007 at 12:56:21AM +0100, Chris Newport wrote: 2) Older OBPs cannot see beyond either 1Gb or 2Gb into a partition depending on version. If your installer puts anything needed for the initial boot process beyond this point you will not be able to boot. [ Affects Sparc32 ] I've got a sun4u, so this shouldn't affect me... 3) The first cylinder of the disk contains the partition information. Most filesystems work around this by not actually using the first cylinder, but Linux Raid does not understand this and it will overwrite the tables. The solution is simple - just create a small partition of one cylinder at cylinder zero and do not use it. [ Affects Linux Raid and possibly oddball filesystems such as XFS only when they start at cylinder zero ] I can't quite reproduce this - my current /dev/sda1 and /dev/sdb1, both of which start at the first cylinder, are in a RAID array, but work fine. 4) If the partition table on the disk was first written by an old version of the Solaris format command the maximum useable size of any partition will be either 1Gb or 2Gb depending on version. Linux will probably not notice and allow you to create a larger partition which will confuse the OBP even if the OBP does not have the limitation in 2) above. The workaround for this is to destroy cylinder zero by filling it with zeros using dd and then use Linux fdisk to create a new BSD table. [ Affects disks initially formatted with old utilities ] I had Solaris on it previously, but I only had Linux parted and fdisk trample over it several times, I never filled it with zeros. Is that really necessary? :) -- 2. That which causes joy or happiness. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: md (software) RAID missing in the installer for sparc
On Tue, 17 Apr 2007, Josip Rodin wrote: 4) If the partition table on the disk was first written by an old version of the Solaris format command the maximum useable size of any partition will be either 1Gb or 2Gb depending on version. Linux will probably not notice and allow you to create a larger partition which will confuse the OBP even if the OBP does not have the limitation in 2) above. The workaround for this is to destroy cylinder zero by filling it with zeros using dd and then use Linux fdisk to create a new BSD table. [ Affects disks initially formatted with old utilities ] I had Solaris on it previously, but I only had Linux parted and fdisk trample over it several times, I never filled it with zeros. Is that really necessary? :) Yes, The table is only created when the disk is first labelled. The table does not change, only the entries in the table. The table contains version information which must be preserved because the data format changed between versions to allow larger pointers. The same problem also shows up on IDE disks, if older utilities were used to label the disk it will always have a maximum size of 8Gb or 37Gb until you zap the table and make a new one. There is also a problem with SILO which I do not fully understand, but it can also have problems looking more than 2047 Mb into a partition. This can sneak up on you if you edit any of SILO's files, the new file can be past the limit and make the system unbootable. It is always best practice to have a small /boot partition at the beginning of the disk. BTW - If you are using RAID for your data you should also mirror swap. Do not use anything other than a simple mirror for swap and do not have more than one swap area on the same spindle. Both Solaris and Linux will try to optimise performance by striping swap data across as many swaps as you have, so having more than one swap per spindle will guarantee serious head thrashing. Maybe someone more knowledgeable will explain the SILO problems. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: md (software) RAID missing in the installer for sparc
On Sun, Apr 01, 2007 at 03:24:03PM +0200, Josip Rodin wrote: It _is_ supported, but the option Use as RAID will not be shown if the current partition starts on sector 0 of the disk because that would overwrite the Sun disklabel info. | The first partition has to be ext3 or fd, not swap because swap writes | from first block and avoid silo block. If swap begins on the cylinder 1, | openprom cannot boot (ther is not MBR on sparc architecture). Further, it seems that this is supported by http://www.openbsd.org/faq/faq14.html#disklabel which says: * (sparc/sparc64) Don't put swap at the very beginning of your disk. -- 2. That which causes joy or happiness. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: md (software) RAID missing in the installer for sparc
On Sun, Apr 01, 2007 at 03:24:03PM +0200, Josip Rodin wrote: It _is_ supported, but the option Use as RAID will not be shown if the current partition starts on sector 0 of the disk because that would overwrite the Sun disklabel info. So, to set up RAID on sparc, first create a small (/boot) partition and then create a second partition to set up as RAID. But... that's not actually supposed to be necessary. | The first partition has to be ext3 or fd, not swap Now I also found that silo-installer postinst knows this, too: # force -t on raid if echo $bootfs | grep -q /dev/md; then raidinstall=y else raidinstall=n fi If software RAID wasn't supposed to be used on the SILO boot device at all, then this code wouldn't be here. Upon finding that if $raidinstall is set, it runs silo with the -t option), I did that myself and it worked fine. -- 2. That which causes joy or happiness. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: md (software) RAID missing in the installer for sparc
On Wednesday 04 April 2007 16:46, Josip Rodin wrote: If software RAID wasn't supposed to be used on the SILO boot device at all, then this code wouldn't be here. Please file a BR against silo-installer with a summary of this thread. pgpTyFbrUdTBq.pgp Description: PGP signature
Re: md (software) RAID missing in the installer for sparc
On Wed, Apr 04, 2007 at 04:57:11PM +0200, Frans Pop wrote: If software RAID wasn't supposed to be used on the SILO boot device at all, then this code wouldn't be here. Please file a BR against silo-installer with a summary of this thread. But there is no problem with silo-installer, it's partman that needs to take care of this. I checked the partman-md bug list, and found #411756, where I've now concurred. silo-installer could have the different, proper sanity check added, but that would be extra, because it would cover the corner case where someone goes behind partman's back, and then returns to d-i just to get silo installed. That's unlikely, since people who know they way around parted/fdisk probably also know how to run silo manually. In fact, even for the less advanced users I think this is a rather small corner case, because you don't have /dev/md* in the shell until you activate the md subsystem, and the most straightforward way to do that is to simply enter partman and through it enter mdcfg :) The main part of mdcfg.sh runs all the right modprobes and mdadm autoscans. -- 2. That which causes joy or happiness. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: md (software) RAID missing in the installer for sparc
On Wednesday 04 April 2007 17:19, Josip Rodin wrote: But there is no problem with silo-installer, it's partman that needs to take care of this. I checked the partman-md bug list, and found #411756, where I've now concurred. No, the bit that does the check in partman is part of silo-installer! http://svn.debian.org/wsvn/d-i/trunk/packages/arch/sparc/silo-installer/finish.d/?rev=0sc=0 /me is kind of expected to know what he's talking about :-) pgpcP585ySZNj.pgp Description: PGP signature
Re: md (software) RAID missing in the installer for sparc
On Wed, Apr 04, 2007 at 05:39:35PM +0200, Frans Pop wrote: But there is no problem with silo-installer, it's partman that needs to take care of this. I checked the partman-md bug list, and found #411756, where I've now concurred. No, the bit that does the check in partman is part of silo-installer! http://svn.debian.org/wsvn/d-i/trunk/packages/arch/sparc/silo-installer/finish.d/?rev=0sc=0 /me is kind of expected to know what he's talking about :-) Yes, but that check that prevents the first partition to be md isn't there, it's in packages/partman/partman-md/choose_method/md/choices -- 2. That which causes joy or happiness. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: md (software) RAID missing in the installer for sparc
On Sun, Apr 01, 2007 at 02:18:11PM +0200, Josip Rodin wrote: [ Fabio M. Di Nitto ] * RAID cannot be selected if we are on sparc AND the partiton starts at 0 otherwise there will partition table corruption happening in the first 512 bytes of the disk. I found another bit of info, from Fabio: https://launchpad.net/ubuntu/+source/silo/+bug/66727/comments/2 (Upon further meddling with my setup, I managed to make my system unbootable again, so I'm still investigating :) -- 2. That which causes joy or happiness. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: md (software) RAID missing in the installer for sparc
Josip Rodin a écrit : On Sun, Apr 01, 2007 at 03:39:37PM +0200, Frans Pop wrote: But... that's not actually supposed to be necessary. Quoting: [...] | The first partition has to be ext3 or fd, not swap because swap | writes from first block and avoid silo block. If swap begins on the | cylinder 1, openprom cannot boot (ther is not MBR on sparc | architecture). This was in reply to another person's question, and that person (who had a problem) had swap as the first partition. I don't see how you conclude one from the other. The man said that it works for him(tm)... that sounds relevant :) I confirm ;-) I have several Sparc (U1, U2, U60, U80, U420) that run fine for a very long time with raid1 partition /boot that start on the first cylinder (Sun disklabel). Silo is installed on partitions, not on whole disk. Regards, JKB -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
md (software) RAID missing in the installer for sparc
Hi, I couldn't help but notice that there is no support for software RAID arrays in the sparc installer. All I found to document it was: partman-md (24) unstable; urgency=low [ Fabio M. Di Nitto ] * RAID cannot be selected if we are on sparc AND the partiton starts at 0 otherwise there will partition table corruption happening in the first 512 bytes of the disk. (NOTE: this will work only once patch for sparc/raid support will make it in parted) [...] -- Frans Pop [EMAIL PROTECTED] Sat, 29 Apr 2006 03:30:04 +0200 Oddly enough, I can't seem to find the problem there, because parted code doesn't seem to have exceptions for sparc... Some more digging excavated me the bug #315009, saying the Use as: physical volume for RAID option is missing. That bug was closed with: Date: Thu, 20 Apr 2006 17:45:22 -0300 [...] parted (1.6.25.1-3) unstable; urgency=low [...] * Apply patch to fix RAID usage in SPARC. Thanks to Fabio Di Nitto [EMAIL PROTECTED] (Closes: #355467) So how come this didn't propagate into debian-installer for etch? -- 2. That which causes joy or happiness. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: md (software) RAID missing in the installer for sparc
On Sunday 01 April 2007 14:18, Josip Rodin wrote: I couldn't help but notice that there is no support for software RAID arrays in the sparc installer. It _is_ supported, but the option Use as RAID will not be shown if the current partition starts on sector 0 of the disk because that would overwrite the Sun disklabel info. So, to set up RAID on sparc, first create a small (/boot) partition and then create a second partition to set up as RAID. pgpSfROIOywgU.pgp Description: PGP signature
Re: md (software) RAID missing in the installer for sparc
On Sun, Apr 01, 2007 at 02:36:15PM +0200, Frans Pop wrote: I couldn't help but notice that there is no support for software RAID arrays in the sparc installer. It _is_ supported, but the option Use as RAID will not be shown if the current partition starts on sector 0 of the disk because that would overwrite the Sun disklabel info. So, to set up RAID on sparc, first create a small (/boot) partition and then create a second partition to set up as RAID. But... that's not actually supposed to be necessary. Quoting: | Date: Tue, 04 Apr 2006 13:12:52 +0200 | From: BERTRAND Joël [EMAIL PROTECTED] | To: debian-sparc@lists.debian.org | | The first partition has to be ext3 or fd, not swap because swap writes | from first block and avoid silo block. If swap begins on the cylinder 1, | openprom cannot boot (ther is not MBR on sparc architecture). This was in reply to another person's question, and that person (who had a problem) had swap as the first partition. -- 2. That which causes joy or happiness. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: md (software) RAID missing in the installer for sparc
On Sunday 01 April 2007 15:24, Josip Rodin wrote: But... that's not actually supposed to be necessary. Quoting: [...] | The first partition has to be ext3 or fd, not swap because swap | writes from first block and avoid silo block. If swap begins on the | cylinder 1, openprom cannot boot (ther is not MBR on sparc | architecture). This was in reply to another person's question, and that person (who had a problem) had swap as the first partition. I don't see how you conclude one from the other. AFAIK RAID also writes its signatures on the first block and this causes the same problem as swap does. (No idea what fd stands for.) Anyway, I trust the sparc porters (Fabio in this case) on this. I may have confused disklabel with silo data. The fact remains that RAID is only supported in D-I on partitions that do not start at the beginning of the disk. pgpfhmnXioxFg.pgp Description: PGP signature
Re: md (software) RAID missing in the installer for sparc
On Sun, Apr 01, 2007 at 03:39:37PM +0200, Frans Pop wrote: But... that's not actually supposed to be necessary. Quoting: [...] | The first partition has to be ext3 or fd, not swap because swap | writes from first block and avoid silo block. If swap begins on the | cylinder 1, openprom cannot boot (ther is not MBR on sparc | architecture). This was in reply to another person's question, and that person (who had a problem) had swap as the first partition. I don't see how you conclude one from the other. The man said that it works for him(tm)... that sounds relevant :) AFAIK RAID also writes its signatures on the first block and this causes the same problem as swap does. (No idea what fd stands for.) fd is the partition table designation of a 'Linux raid autodetect' partition (like 83 is ext2/3). The fact remains that RAID is only supported in D-I on partitions that do not start at the beginning of the disk. I didn't notice it, because I went for the first partition, saw it was not there, and didn't try for the rest. I can't imagine many other users doing anything differently. Perhaps an error is in order, rather than omitting the option altogether :) -- 2. That which causes joy or happiness. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: md (software) RAID missing in the installer for sparc
On Sun, Apr 01, 2007 at 04:19:19PM +0200, Josip Rodin wrote: On Sun, Apr 01, 2007 at 03:39:37PM +0200, Frans Pop wrote: But... that's not actually supposed to be necessary. Quoting: [...] | The first partition has to be ext3 or fd, not swap because swap | writes from first block and avoid silo block. If swap begins on the | cylinder 1, openprom cannot boot (ther is not MBR on sparc | architecture). This was in reply to another person's question, and that person (who had a problem) had swap as the first partition. I don't see how you conclude one from the other. The man said that it works for him(tm)... that sounds relevant :) Relevance wasn't questioned; your conclusion was questioned. Regardless of this quote, I can tell you from experience that it does not work to have the first partition be a raid partition and start from cylinder 0. This is the first time I've heard that you can't boot if the first partition is swap and starts at cyl 1. Sounds bogus to me. a -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: md (software) RAID missing in the installer for sparc
On Sun, Apr 01, 2007 at 12:56:19PM -0700, Andrew Sharp wrote: | The first partition has to be ext3 or fd [...] The man said that it works for him(tm)... that sounds relevant :) Relevance wasn't questioned; your conclusion was questioned. My conclusion was that he said that a separate non-RAID partition is not actually necessary, which is exactly what he wrote... See the whole post at http://lists.debian.org/debian-sparc/2006/04/msg00021.html Regardless of this quote, I can tell you from experience that it does not work to have the first partition be a raid partition and start from cylinder 0. This is the first time I've heard that you can't boot if the first partition is swap and starts at cyl 1. Sounds bogus to me. I guess I'll just have to test and see. -- 2. That which causes joy or happiness. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
