kexec-tools/mkdumprd.8
Lianbo Jiang cd7264705d Doc: improve mkdumprd man page
Currently, when generating a kdump initramfs, mkdumprd will determine
how much disk space is available, if the dump target's available space
is not greater than the total system memory, mkdumprd will print a
warning to remind that there might not be enough space to save a vmcore.

Some users are complaining that mkdumprd overestimates the needed size.
But actually, the warning covers extreme scenarios such as the slab
explodes with non-zero data or a full vmcore, etc. Therefore, need to
prevent users from having minimum disk space for crash dump.

In view of this, add some descriptions to clarify it in mkdumprd man
page.

Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
Acked-by: Kairui Song <kasong@redhat.com>
2020-12-11 14:05:08 +08:00

40 lines
1.7 KiB
Groff

.TH MKDUMRD 8 "Fri Feb 9 2007"
.SH NAME
mkdumprd \- creates initial ramdisk images for kdump crash recovery
.SH SYNOPSIS
\fBmkdumprd\fR [OPTION]
.SH DESCRIPTION
\fBmkdumprd\fR creates an initial ram file system for use in conjunction with
the booting of a kernel within the kdump framework for crash recovery.
\fBmkdumprds\fR purpose is to create an initial ram filesystem capable of copying
the crashed systems vmcore image to a location specified in \fI/etc/kdump.conf
\fBmkdumprd\fR interrogates the running system to understand what modules need to
be loaded in the initramfs (based on configuration retrieved from
\fI/etc/kdump.conf)\fR
\fBmkdumprd\fR add a new \fBdracut\fR module 99kdumpbase and use \fBdracut\fR
utility to generate the initramfs. When generating a kdump initramfs, \fBmkdumprd\fR
will determine how much disk space is available, if the dump target's available
space is not greater than the total system memory, \fBmkdumprd\fR will print a
warning to remind that there might not be enough space to save a vmcore. The
warning covers extreme scenarios such as the slab explodes with non-zero data or
a full vmcore, etc. Therefore, need to prevent users from having minimum disk
space for crash dump.
\fBmkdumprd\fR was not intended for casual use outside of the service
initialization script for the kdump utility, and should not be run manually. If
you require a custom kdump initramfs image, it is suggested that you use the
kdump service infrastructure to create one, and then manually unpack, modify and
repack the image.
.SH OPTIONS
.TP
All options here are passed to dracut directly, please refer \fBdracut\fR docs
for the info.
.SH "SEE ALSO"
.BR dracut (8)