Date: Mon, 27 Jan 1997 17:10:25 +0100 (MET) From: Greg Lehey <grog@lemis.de> To: kline@tera.com (Gary Kline) Cc: questions@FreeBSD.org (FreeBSD Questions) Subject: Re: can anybody make sense of this info? Message-ID: <199701271610.RAA12060@freebie.lemis.de> In-Reply-To: <199701211838.KAA09290@athena.tera.com> from Gary Kline at "Jan 21, 97 10:38:33 am"
next in thread | previous in thread | raw e-mail | index | archive | help
Gary Kline writes: > > > > I've been trying to get a new SCSI drive mounted as sd1 for the > past 2 weeks. I keep stumbling into obstacles.... It's closer > and closer, but not-quite. > > Every time I reboot, dmesg prints this error: > > > sd1: invalid primary partition table: no magic > sd1: invalid primary partition table: no magic > > > Can anybody help me get rid of this error so that the mount of > sd1c is clean? > > In /etc/fstab I have: > > (...) > ## SCSI drive #2 > # > /dev/sd1c /usr/local2 ufs rw 1 1 > proc /proc procfs rw 0 0 > > When the system is already booted I can mount/umount > /dev/sd1 -t ufs /mnt > /dev/sd1c -t ufs /mnt > > Trying ``mount -t ufs /dev/sd1a /mnt'' fails because slice "a" > is meant for root, according to /etc/disktab: > > # a == root > # b == swap > # c == d == whole disk And c is the whole disk. I don't know where you get d from, but that's just a regular partition, at least nowadays. > # e == /var > # f == scratch > # h == /usr With the exception of partition c, all of these are recommendations. > I can mount either sd1 or sd1c on <<wherever>> and it works. > But on rebooting, there is that ``invalid primary partition'' > err. Upon coming up, however, /dev/sd1* _is_ in the mount > table. `mount' finds it. > > Here is my hacked /etc/disktab entry for the drive: > > > ibm3720|IBM 720MB SCSI:\ >> dt=SCSI:ty=winchester:se#512:nt#4:ns#91:nc#3875:rm#4500: \ >> pc#1423360:oc#0: \ >> tc=4.2BSD:bc#4096:fc#512: > > > Does this look right? No. > Am I missing something that would allow newfs to stick in the > magic number? Yes. The problem is that c is supposed to be the complete disk. Typically, if you only want a single partition on your disk (a very good idea, IMO, though many people don't like it), you should choose another partition. I tend to choose partition a if it's a root file system (which means that only one disk has a partition a), b if it's a swap partition, or h for anything else. This isn't quite the same as sysinstall will give you when you install by default: it'll put /usr on partition e. There's not much choice between the two, but I prefer h. For example, my machine has (locally): === grog@freebie (/dev/ttyp8) ~ 28 -> df Filesystem 1024-blocks Used Avail Capacity Mounted on /dev/wd0a 30206 21850 5940 79% / /dev/wd0s1e 1152422 951538 108692 90% /usr /dev/sd0h 875927 602152 203701 75% /home /dev/sd1h 1841395 898420 795663 53% /src /dev/sd2h 3927761 3213385 400155 89% /S You *can* have more than one swap. I've heard rumours that some utilities can get confused if it's not on partition b, though that would mean a bug in that utility, but there's no good reason not to put it on b. Thus, on the same system: === grog@freebie (/dev/ttyp8) ~ 29 -> pstat -s Device 1024-blocks Used Avail Capacity Type /dev/wd0s1b 51200 17152 33984 34% Interleaved /dev/sd0b 98175 17052 81059 17% Interleaved Total 149247 34204 115043 23% Getting back to your problem: by putting your file system on slice c, you've obviously confused something. At the moment it doesn't matter, apart from this irritating message, but when you upgrade you could conceivably have problems. A more typical /etc/disktab entry for your disk might be: ibm3720|IBM 720MB SCSI:\ dt=SCSI:ty=winchester:se#512:nt#4:ns#91:nc#3875:rm#4500: \ pc#1423360:oc#0:bc#4096:fc#512: ph#1423360:oh#0:th=4.2BSD:bh#4096:fh#512: To be honest, I'm not completely happy with this explanation. We're defining the h partition to be identical with the c partition. This is kosher, and it doesn't give the 'no magic' messages, but I'm not 100% sure why. Is there possibly something else that you have done that would explain the difference (maybe the 'dangerously dedicated' mode)? Or maybe it's because you specified 'tc=4.2BSD'. Please let me know what happens if you change anything. Greg
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199701271610.RAA12060>