first of all, sorry about my english...I´m a spanish newbie to this marvelous OS and i have just a couple of doubts...u know? :-)
1) how big should my swap partition be if i installed debian 2.2r3 or FreeBSD 4.x on a AMD k7 1400Mhz with 512Mb of Random Access Memory?
i heard that those OS... (1 Reply)
I run a dual boot WinXP/Red Hat 8 system on my laptop. Since my hard drive is inherently small(laptop) I am trying to creat a swap partition for keeping mutually used files such as music/video etc... I have created a 2.5GB Fat32 partition with Partition Magic Pro and have windows recognizing the... (2 Replies)
What does a swap partition do exactly? I was messing arround with a linux machine at my school and i deleted the swap partition using fdisk and then rebooted the machine and it worked fine and wrote a swap partition back in...lol. Is it a nessary part of the OS to use that partition? (7 Replies)
Dear All
Anyone can help me what is the problem of swap partition? swap partition is showing mounted in df -h command output.
Regards
prakash (1 Reply)
Hi,
running mount, I get the following, no part1 swap
as part1 swap has been created
and is listed below.
System works fine anyway.
As I cannot unmount part1, what is a standard procedure to make part1 on.
Jack
=============
..
$ free
total used free shared buffers cached
Mem:... (2 Replies)
Hello Experts,
Is there a way to generate Universally Unique identifiers on all Unix flavours such as Solaris, RHELinux,Suse Linux, MacOS,HP UX etc?
If i can get a system command or a system call or an algorithm/script/program to generate a unique identifier, it will be helpful.
Thanks in... (1 Reply)
Greetings. I've been into computers since the '80s, but this is my first attempt at Linux.
I'm installing Debian Lenny on a PIII 733 with 10GB hard drive and 512MB Ram. I intend to use the machine primarily as a development server, with things like mySQL, Apache, php, etc.
I don't really want... (22 Replies)
I thought I had figured this out at one point, but I can't remember. Is there a way/command to get the UUIDs of a disk's partitions/slices in FreeBSD? Linux has the blkid command, which doesn't seem to be available. (2 Replies)
Discussion started by: AntumDeluge
2 Replies
LEARN ABOUT SUNOS
mkswap
MKSWAP(8) System Administration MKSWAP(8)NAME
mkswap - set up a Linux swap area
SYNOPSIS
mkswap [options] device [size]
DESCRIPTION
mkswap sets up a Linux swap area on a device or in a file.
The device argument will usually be a disk partition (something like /dev/sdb7) but can also be a file. The Linux kernel does not look at
partition IDs, but many installation scripts will assume that partitions of hex type 82 (LINUX_SWAP) are meant to be swap partitions.
(Warning: Solaris also uses this type. Be careful not to kill your Solaris partitions.)
The size parameter is superfluous but retained for backwards compatibility. (It specifies the desired size of the swap area in 1024-byte
blocks. mkswap will use the entire partition or file if it is omitted. Specifying it is unwise - a typo may destroy your disk.)
After creating the swap area, you need the swapon command to start using it. Usually swap areas are listed in /etc/fstab so that they can
be taken into use at boot time by a swapon -a command in some boot script.
WARNING
The swap header does not touch the first block. A boot loader or disk label can be there, but it is not a recommended setup. The recom-
mended setup is to use a separate partition for a Linux swap area.
mkswap, like many others mkfs-like utils, erases the first partition block to make any previous filesystem invisible.
However, mkswap refuses to erase the first block on a device with a disk label (SUN, BSD, ...).
OPTIONS -c, --check
Check the device (if it is a block device) for bad blocks before creating the swap area. If any bad blocks are found, the count is
printed.
-f, --force
Go ahead even if the command is stupid. This allows the creation of a swap area larger than the file or partition it resides on.
Also, without this option, mkswap will refuse to erase the first block on a device with a partition table.
-L, --label label
Specify a label for the device, to allow swapon by label.
-p, --pagesize size
Specify the page size (in bytes) to use. This option is usually unnecessary; mkswap reads the size from the kernel.
-U, --uuid UUID
Specify the UUID to use. The default is to generate a UUID.
-v, --swapversion 1
Specify the swap-space version. (This option is currently pointless, as the old -v 0 option has become obsolete and now only -v 1
is supported. The kernel has not supported v0 swap-space format since 2.5.22 (June 2002). The new version v1 is supported since
2.1.117 (August 1998).)
-h, --help
Display help text and exit.
-V, --version
Display version information and exit.
NOTES
The maximum useful size of a swap area depends on the architecture and the kernel version.
The maximum number of the pages that is possible to address by swap area header is 4294967295 (UINT_MAX). The remaining space on the swap
device is ignored.
Presently, Linux allows 32 swap areas. The areas in use can be seen in the file /proc/swaps
mkswap refuses areas smaller than 10 pages.
If you don't know the page size that your machine uses, you may be able to look it up with "cat /proc/cpuinfo" (or you may not - the con-
tents of this file depend on architecture and kernel version).
To set up a swap file, it is necessary to create that file before initializing it with mkswap, e.g. using a command like
# fallocate --length 8GiB swapfile
Note that a swap file must not contain any holes. Using cp(1) to create the file is not acceptable. Neither is use of fallocate(1) on
file systems that support preallocated files, such as XFS or ext4, or on copy-on-write filesystems like btrfs. It is recommended to use
dd(1) and /dev/zero in these cases. Please read notes from swapon(8) before adding a swap file to copy-on-write filesystems.
ENVIRONMENT
LIBBLKID_DEBUG=all
enables libblkid debug output.
SEE ALSO fdisk(8), swapon(8)AVAILABILITY
The mkswap command is part of the util-linux package and is available from https://www.kernel.org/pub/linux/utils/util-linux/.
util-linux March 2009 MKSWAP(8)