Gentoo Archives: gentoo-releng

From: Denys Fedoryshchenko <denys@××××××××.lb>
To: gentoo-releng@l.g.o
Subject: Re: [gentoo-releng] kexec compiled into kernel
Date: Mon, 28 Jan 2008 16:26:45
Message-Id: 20080128162023.M47571@visp.net.lb
In Reply to: Re: [gentoo-releng] kexec compiled into kernel by Andrew Gaffney
1 For example you compile new kernel, and you want to test it without
2 installing in boot loader. It is very useful, especially when it is remote
3 machine with grub, grub "one time load" not so useful like lilo -R, plus each
4 operation with boot loader causing risk to make system inoperable, even by
5 typo.
6
7 1)compile tools
8 emerge kexec-tools
9 2)Load kernel to memory (kexec have to be compiled in kernel)
10 kexec -l /path/kernelname --append="root=/dev/rootdevice panic=5"
11 3)When you are ready (sync, also highly recommended to unmount partitions or
12 remount read-only), LAUNCH! :-)
13 kexec -e
14
15 system will start booting new kernel, without complete hardware reset. There
16 is some issues with buggy drivers, like intel wireless 3945, i wrote
17 bugreport to intel, and probably will be fixed soon. But hardware cases with
18 kexec very rare, and it works just great for me.
19
20 They only one thing stopping me to contribute few scripts and tips - my
21 crappy english.
22
23 On Mon, 28 Jan 2008 10:17:58 -0600, Andrew Gaffney wrote
24 > Denys Fedoryshchenko wrote:
25 > > Hi
26 > >
27 > > Is it possible to compile in kernel kexec support? at least for
28 architectures
29 > > where it is well supported.
30 > >
31 > > It is very handy, when Gentoo installed on PC remotely on regular PC,
32 when
33 > > people there just boot CD and set ip, and leave location for few days.
34 > > It is not possible to eject CD on remote PC, cause on reboot BIOS usually
35 > > closing tray. kexec will let to reboot system to newly compiled kernel
36 > > without full reboot, avoiding system to boot from CD again. Remote tech's
37 on
38 > > location can remove CD later, when it is comfortable for them.
39 >
40 > How is kexec used? Are there commandline utilities for it? Is it
41 > triggered through a /proc interface?
42 >
43 > --
44 > Andrew Gaffney http://dev.gentoo.org/
45 ~agaffney/
46 > Gentoo Linux Developer Catalyst/Installer + x86 release
47 coordinator
48 > --
49 > gentoo-releng@l.g.o mailing list
50
51
52 --
53 Denys Fedoryshchenko
54 Technical Manager
55 Virtual ISP S.A.L.
56
57 --
58 gentoo-releng@l.g.o mailing list