Date: Mon, 02 Oct 2000 21:08:37 -0700 From: xavian anderson macpherson <professional3d@home.com> To: "freebsd-questions@FreeBSD.ORG" <freebsd-questions@FreeBSD.ORG> Subject: answers from the abyss for vinum Message-ID: <39D95BC5.956E41D5@home.com>
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this is what was sent to me. i hope that after reading the answer below, some of you will have a higher level of appreciation for my hesitancy. i don't think that i ever got as far as booting lvm with linux. i was having alot of problems with booting linux (without lvm) anyway. i don't remember if linux can boot from an lvm. i just checked the man page; it doesn't say anything about this. i don't think it's a problem though, or it would have said so in the suse book. i just checked the book. in fact, it doesn't say anything but the single line below. the amazing thing is that i managed to set it up without any real documentation! as convoluted as it was i did it the first time through! the official LVM-Howto is located at http://linux.msede.com/lvm ========================================================= I do not think that you can boot from a vinum volume: (from http://www.vinumvm.org/vinum/wishlist.html) >>> this was not in the book; so how was reading supposed to answer this. but somehow, i'm supposed to be at fault. >>> It's currently not possible to mount the root file system on a Vinum volume. This is a chicken and egg problem: You can't start Vinum until the kernel is running, and the kernel needs to be mounted somewhere. There are at least four different possible ways to implement this: 1.Teach the bootstrap code about Vinum so that it could start Vinum and load directly from a Vinum volume. This is unlikely to be viable, since Vinum needs to know too much about the kernel environment. 2.Create a separate boot file system and put the kernel in there, then start Vinum and the root file system. This is the System V way, but I don't like it too much. 3.Create an MFS root file system. This effectively lives in swap, but there's no problem there. We'd need an easier way to build MFS kernels. 4.Boot normally, start Vinum and then mount the root file system on top of the old root file system. This might work, up to a point: you can mount a file system on any mount point, even if files are open in the hierarchy below the mount point. Unfortunately, there are a number of problems with this approach. In particular, you can't close all files on the old root partition, which means that you're not completely resilient. In addition, if you boot from the Vinum partition as a normal disk partition (which is possible and seems to make sense), you'll have consistency problems if you change a file on one partition and not the other, since the system sees the two partitions as separate. One possibility here would be for the mount operation to go through the vnodes for each open file and change them to point to the Vinum volume. It's likely that this will be a difficult operation to perform. Status: I'm still thinking about this one. It's the single most asked-for feature, and I'm very open to suggestions about how to implement it. So, it seems that you wont have a partial install, and then a move. You'll have a full install, and a post-install configuration of vinum for all remaining slices. As I mentioned, I have not used vinum (although I am now very interested in it), so I cannot tell you exactly how to set it up. >From what I gather, what your question boils down to is: "I want to install FreeBSD, and I want to set up my filesystem using vinum. How do I do this?" Perhaps it is best to allow someone more qualified (Greg :)) to answer this question for you, as I have no working knowledge of vinum. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message
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