Linux Commands


This page is a work in progress,

Information will be added as new commands are encountered.

Some commands listed may not work in your particular distribution.

I have learned through years of working in Linux that there are always functions and commands for the command line that you can and will have a use for. The purpose of this page is to give a brief description of many of those commands. If you would like further information consult the man pages for the particular command, information on the man pages can be found in Linux Application Documentation.



lilo - install boot loader
lilo installs a boot loader that will be activated the next time you boot your system. The default configuration file /etc/lilo.conf (see 'man lilo.conf') will contain most options, but many, including those which override the configuration file, may be specified on the command line.

Console Functions

agetty - alternative Linux getty
agetty opens a tty port, prompts for a login name and invokes the /bin/login command. It is normally invoked by init(8)

consoletype - print type of the console connected to standard input
consoletype prints the type of console connected to standard input, and checks whether the console connected to standard input is the current foreground virtual console.

getty - sets terminal mode, speed, and conditions port
Getty is the second in the series of programs ( init(1m), getty(1m), login(1m), and shell [bash, sh, or others]), used by the system to connect the user to the system (i.e., allow the user to login and thus gain access to system resources). Note that telnet has it's own login process and does not use getty.

sulogin - Single-user login
sulogin is invoked by init prior to allowing the user access to the system when in single user mode. This feature may only be available on certain systems where init has been modified accordingly, or where the /etc/inittab has an entry for a single user login.

Data Backup

rmt -- remote magtape protocol module
Rmt is a program used by the remote dump and restore programs in manipulating a magnetic tape drive through an interprocess communication connection. Rmt is normally started up with an rexec(3) or rcmd(3) call.

stinit - initialize SCSI magnetic tape drives
This manual page documents the tape control program stinit can used to initialize SCSI tape drive modes at system startup, after loading the tape driver as module, or after introduction of new device to the SCSI subsystem at run-time.

Filesystem Creation

jfs_mkfs - create a JFS formatted partition
jfs_mkfs is used to create (format) a JFS partition. jfs_mkfs must be run as root.

mkdosfs - create an MS-DOS file system under Linux
mkdosfs is used to create an MS-DOS file system under Linux on a device (usually a disk partition).

mke2fs - create an ext2/ext3 filesystem
mke2fs is used to create an ext2/ext3 filesystem (usually in a disk partition).

mkfs - build a Linux file system
mkfs is used to build a Linux file system on a device, usually a hard disk partition.

mkfs.bfs - make an SCO bfs filesystem
mkfs.bfs creates an SCO bfs file-system on a block device (usually a disk partition or a file accessed via the loop device).

mkfs.minix - make a Linux MINIX filesystem
mkfs.minix creates a Linux MINIX file-system on a device (usually a disk partition).

mkfs.xfs - construct an XFS filesystem
mkfs.xfs constructs an XFS filesystem by writing on a special file using the values found in the arguments of the command line. It is invoked automatically by mkfs(8) when mkfs is given the -t xfs option.

mklost+found - create a lost+found directory on a mounted Linux second extended file system
mklost+found is used to create a lost+found directory in the current working directory on a Linux second extended file system. There is normally a lost+found directory in the root directory of each filesystem.

mkreiserfs - The create tool for the Linux ReiserFS filesystem.
mkreiserfs creates a Linux ReiserFS filesystem on a device (usually a disk partition).

/sbin/mkrescue - make a bootable rescue floppy or CD using the default kernel specified in lilo.conf.
mkrescue takes its specifation for the kernel from the default image specified in /etc/lilo.conf.

mkswap - set up a Linux swap area
mkswap sets up a Linux swap area on a device or in a file.

Filesystem Debugging and Repair

debugfs - ext2/ext3 file system debugger
The debugfs program is an interactive file system debugger. It can be used to examine and change the state of an ext2 file system.

debugreiserfs - The debugging tool for the ReiserFS filesystem.
debugreiserfs sometimes helps to solve problems with reiserfs filesystems. When run without options it prints the super block of the ReiserFS filesystem found on the device.

dosfsck - check and repair MS-DOS file systems
dosfsck verifies the consistency of MS-DOS file systems and optionally tries to repair them.

dumpe2fs - dump ext2/ext3 filesystem information
dumpe2fs prints the super block and blocks group information for the filesystem present on device.

e2fsck - check a Linux ext2/ext3 file system
e2fsck is used to check a Linux second extended file system (ext2fs). E2fsck also supports ext2 filesystems containing a journal, which are also sometimes known as ext3 filesystems, by first applying the journal to the filesystem before continuing with normal e2fsck processing.

e2image - Save critical ext2/ext3 filesystem metadata to a file
The e2image program will save critical ext2 or ext3 filesystem metadata located on device to a file specified by image-file.

findfs - Find a filesystem by label or UUID
findfs will search the disks in the system looking for a filesystem which has a label matching label or a UUID equal to uuid. If the filesystem is found, the device name for the filesystem will be printed on stdout.

fsck - check and repair a Linux file system
fsck is used to check and optionally repair one or more Linux file systems. filesys can be a device name (e.g. /dev/hdc1, /dev/sdb2), a mount point (e.g. /, /usr, /home), or an ext2 label or UUID specifier (e.g. UUID=8868abf6-88c5-4a83-98b8-bfc24057f7bd or LABEL=root). Normally, the fsck program will try to handle filesystems on different physical disk drives in parallel to reduce the total amount of time needed to check all of the filesystems.

jfs_debugfs - shell-type JFS file system editor
jfs_debugfs is a program which can be used to perform various low-level actions on a JFS formatted device.

jfs_fsck - initiate replay of the JFS transaction log, and check and repair a JFS formatted device
fs_fsck is used to replay the JFS transaction log, check a JFS formatted device for errors, and fix any errors found.

jfs_fscklog - extract a JFS fsck service log into a file and/or format and display the extracted file
jfs_fscklog with option -e device extracts the contents of either the most recent or immediately prior (specified with option -p) JFS fsck service log from the specified device, and writes the output to a file.

jfs_logdump - dump a JFS formatted device's journal log
jfs_logdump dumps the contents of the journal log from the specified JFS formatted device into output file ./jfslog.dmp.

reiserfsck - The checking tool for the ReiserFS filesystem.
Reiserfsck searches for a Reiserfs filesystem on a device, replays any necessary transactions, and either checks or repairs the file system.

xfs_repair - repair an XFS filesystem
xfs_repair is a parallelized version of xfs_repair(1m) that repairs corrupt or damaged XFS filesystems (see xfs(5)).

xfsrestore - XFS filesystem incremental restore utility
xfsrestore restores filesystems from dumps produced by xfsdump(8). Two modes of operation are available: simple and cumulative.

Filesystem Modification

e2label - Change the label on an ext2/ext3 filesystem
e2label will display or change the filesystem label on the ext2 filesystem located on device.

jfs_tune - adjust tunable file system parameters on JFS
jfs_tune adjusts tunable parameters on a Linux JFS file system or external journal. jfs_tune must be run as root.

pivot_root - change the root file system
pivot_root moves the root file system of the current process to the directory put_old and makes new_root the new root file system. Since pivot_root(8) simply calls pivot_root(2), we refer to the man page of the latter for further details.

reiserfstune - The tunning tool for the ReiserFS filesystem.
reiserfstune is used for tuning the ReiserFS. It can change two journal parameters (the journal size and the maximum transaction size), and it can move the journal's location to a new specified block device.

resize2fs - ext2/ext3 file system resizer
The resize2fs program will resize ext2 or ext3 file systems. It can be used to enlarge or shrink an unmounted file system located on device.

resize_reiserfs - resizer tool for the ReiserFS filesystem
The resize_reiserfs tool resizes an unmounted reiserfs file system. It enlarges or shrinks an reiserfs file system located on a device so that it will have size bytes or size=old_size +(-) size bytes if the + or - prefix is used.

tune2fs - adjust tunable filesystem parameters on ext2/ext3 filesystems
tune2fs allows the system administrator to adjust various tunable filesystem parameters on Linux ext2/ext3 filesystems.

General Administration

adjtimex - display or set the kernel time variables

clock - Determine processor time
The clock() function returns an approximation of processor time used by the program.

halt, reboot, poweroff - stop the system.
Halt notes that the system is being brought down in the file /var/log/wtmp, and then either tells the kernel to halt, reboot or poweroff the system.

hwclock - query and set the hardware clock (RTC)
hwclock is a tool for accessing the Hardware Clock. You can display the current time, set the Hardware Clock to a specified time, set the Hardware Clock to the System Time, and set the System Time from the Hardware Clock.

init, telinit - process control initialization
Init is the parent of all processes. Its primary role is to create processes from a script stored in the file /etc/inittab (see inittab(5)). This file usually has entries which cause init to spawn gettys on each line that users can log in. It also controls autonomous processes required by any particular system.

killall5 -- send a signal to all processes.
killall5 is the SystemV killall command. It sends a signal to all processes except kernel threads and the processes in its own session, so it won't kill the shell that is running the script it was called from. Its primary (only) use is in the rc scripts found in the /etc/init.d directory.

/sbin/ldconfig - configure dynamic linker run time bindings
ldconfig creates the necessary links and cache to the most recent shared libraries found in the directories specified on the command line, in the file /etc/, and in the trusted directories (/lib and /usr/lib). The cache is used by the run-time linker, or ldconfig checks the header and filenames of the libraries it encounters when determining which versions should have their links updated.

runlevel -- find the current and previous system runlevel.
Runlevel reads the system utmp file (typically /var/run/utmp) to locate the runlevel record, and then prints the previous and current system runlevel on its standard output, separated by a single space. If there is no previous system runlevel, the letter N will be printed instead.

shutdown - bring the system down
shutdown brings the system down in a secure way. All logged-in users are notified that the system is going down, and login(1) is blocked.

sln - static ln
sln symbolically links dest to source. It is statically linked, needing no dynamic linking at all. Thus sln is useful to make symbolic links to dynamic libraries if the dynamic linking system for some reason is non-functional.

swapon, swapoff - enable/disable devices and files for paging and swapping
Swapon is used to specify devices on which paging and swapping are to take place.


isapnp - Configure ISA Plug-and-Play devices.
isapnp will carry out the instructions provided in the conffile to configure ISA PnP cards.

lspci - list all PCI devices
lspci is a utility for displaying information about all PCI buses in the system and all devices connected to them.

lspcmcia, pccardctl - PCMCIA card control utility
pccardctl is used to monitor and control the state of PCMCIA sockets. If a socket number is specified, the command will be applied to just one socket; otherwise, all sockets will be affected.

lsusb - list USB devices
lsusb is a utility for displaying information about USB buses in the system and the devices connected to them.

pccardctl - PCMCIA card control utility
pccardctl is used to monitor and control the state of PCMCIA sockets. If a socket number is specified, the command will be applied to just one socket; otherwise, all sockets will be affected.

plipconfig - fine tune PLIP device parameters
Plipconfig is used to (hopefully) improve PLIP performance by changing the default timing parameters used by the PLIP protocol. Results are dependent on the parallel port hardware, cable, and the CPU speed of each machine on each end of the PLIP link.

pnpdump - Dump ISA Plug-And-Play devices resource information
pnpdump will scan all the ISA PnP cards, dumping their resource data to stdout. The resource data is supposed to be a description of the resources (IO ports, interrupts, DMA channels) that the card would like, or needs, to use to work. It is stored in a small ROM on the card, which can be read as part of the Plug and Play configuration process.

rdev - query/set image root device, RAM disk size, or video mode
With no arguments, rdev outputs an /etc/mtab line for the current root file system. With no arguments, ramsize, vidmode, and rootflags print usage information.

setpci - configure PCI devices
setpci is a utility for querying and configuring PCI devices.

setserial - get/set Linux serial port information
setserial is a program designed to set and/or report the configuration information associated with a serial port.

Hard Disk Commands

badblocks - search a device for bad blocks
badblocks is used to search for bad blocks on a device (usually a disk partition).

blkid - command-line utility to locate/print block device attributes
The blkid program is the command-line interface to working with libuuid(3) library. It can determine the type of content (e.g. filesystem, swap) a block device holds, and also attributes (tokens, NAME=value pairs) from the content metadata (e.g. LABEL or UUID fields).

blockdev - call block device ioctls from the command line
The utility blockdev allows one to call block device ioctls from the command line.

elvtune - I/O elevator tuner
elvtune allows to tune the I/O elevator per blockdevice queue basis. The tuning can be safely done at runtime. Tuning the elevator means being able to change disk performance and interactiveness. In the output of elvtune the address of the queue tuned will be shown and it can be considered as a queue ID. For example multiple partitions in the same harddisk will share the same queue and so tuning one partition will be like tuning the whole HD.

fdisk - Partition table manipulator for Linux
Hard disks can be divided into one or more logical disks called partitions. This division is described in the partition table found in sector 0 of the disk.

filefrag - report on file fragmentation
filefrag reports on how badly fragmented a particular file might be. It makes allowances for indirect blocks for ext2 and ext3 filesystems, but can be used on files for any filesystem.

fstab-decode - run a command with fstab-encoded arguments
fstab-decode decodes escapes in the specified ARGUMENTs and uses them to run COMMAND. The argument escaping uses the same rules as path escaping in /etc/fstab, /etc/mtab and /proc/mtab.

jaztool, ziptool - Tool for IOMega JAZ and ZIP drives
Disk write-protection is done by software for IOMega's JAZ and ZIP drives. jaztool and ziptool make these features available for Linux. Before performing any protection mode changes, it is checked that <device> is actually a JAZ or ZIP drive and that no partition of the inserted disk is currently mounted.

losetup - set up and control loop devices
losetup is used to associate loop devices with regular files or block devices, to detach loop devices and to query the status of a loop device. If only the loop_device argument is given, the status of the corresponding loop device is shown.

mdadm - manage MD devices aka Linux Software Raid.
RAID devices are virtual devices created from two or more real block devices. This allows multiple devices (typically disk drives or partitions there-of) to be combined into a single device to hold (for example) a single filesystem. Some RAID levels include redundancy and so can survive some degree of device failure.

mount - mount a file system
All files accessible in a Unix system are arranged in one big tree, the file hierarchy, rooted at /. These files can be spread out over several devices. The mount command serves to attach the file system found on some device to the big file tree. Conversely, the umount(8) command will detach it again.

scsi_id - retrieve and generate a unique SCSI identifier
scsi_id queries a SCSI device via the SCSI INQUIRY vital product data (VPD) page 0x80 or 0x83 and uses the resulting data to generate a value that is unique across all SCSI devices that properly support page 0x80 or page 0x83.

umount - unmount file systems
The umount command detaches the file system(s) mentioned from the file hierarchy. A file system is specified by giving the directory where it has been mounted. Giving the special device on which the file system lives may also work, but is obsolete, mainly because it will fail in case this device was mounted on more than one directory.

vol_id - probe filesystem type and read label and uuid
vol_id is usually called from a udev rule, to provide udev with the filesystem type, the label and the uuid of a volume. It supports most of the common filesystem formats and detects various raid setups to prevent the recognition of raid members as a volume with a filesystem.

Kernel Modifications

depmod -- program to generate modules.dep and map files.
depmod creates a list of module dependencies, by reading each module under /lib/modules/version and determining what symbols it exports, and what symbols it needs.

insmod -- simple program to insert a module into the Linux Kernel
insmod is a trivial program to insert a module into the kernel: if the filename is a hyphen, the module is taken from standard input. Most users will want to use modprobe(8) instead, which is cleverer.

lsmod -- program to show the status of modules in the Linux Kernel
lsmod is a trivial program which nicely formats the contents of the /proc/modules, showing what kernel modules are currently loaded.

mkinitrd - create or rebuilt an initrd (initial ramdisk) using initramfs (simple cpio+gzip).
mkinitrd is used to build an initial ramdisk. An initial ramdisk is a very small set of files that are loaded into RAM and "mounted" (as initramfs doesn't actually use a filesystem) as the kernel boots (before the main root filesystem is mounted). The usual reason to use an initrd is because you need to load kernel modules before mounting the root partition. Usually these modules are required to support the filesystem used by the root partition (ext3, reiserfs, xfs), or perhaps the controller that the hard drive is attached to (SCSI, RAID, etc). Essentially, there are so many different options available in modern Linux kernels that it isn't practical to try to ship many different kernels to try to cover everyone's needs. It's a lot more flexible to ship a generic kernel and a set of kernel modules for it.

modinfo -- program to show information about a Linux Kernel module
modinfo extracts information from the Linux Kernel modules given on the command line.

modprobe - program to add and remove modules from the Linux Kernel
modprobe intelligently adds or removes a module from the Linux kernel: note that for convenience, there is no difference between _ and - in module names. modprobe looks in the module directory /lib/modules/`uname -r` for all the modules and other files, except for the optional /etc/modprobe.conf configuration file and /etc/modprobe.d directory (see modprobe.conf(5)).

rmmod -- simple program to remove a module from the Linux Kernel
rmmod is a trivial program to remove a module from the kernel. Most users will want to use modprobe(8) instead, with the -r option.

sysctl - configure kernel parameters at runtime
sysctl is used to modify kernel parameters at runtime. The parameters available are those listed under /proc/sys/. Procfs is required for sysctl(8) support in Linux. You can use sysctl(8) to both read and write sysctl data.

tc - show / manipulate traffic control settings
Tc is used to configure Traffic Control in the Linux kernel.

udevd - event managing daemon
udevd listens to kernel uevents and passes the incoming events to udev. It ensures the right event order and takes care, that events for child devices are delayed until the parent has finished the device handling.

udevsettle - wait until queued kernel/udev events are handled
Waits watching the udev event queue and exits if all current events are handled.

udevtrigger - request kernel devices events for coldplug
Trigger kernel device uevents to replay missing events at system coldplug.

usbmodules - List kernel driver modules available for a plugged in USB device
usbmodules lists driver modules that may be able to manage interfaces on currently plugged in USB devices. usbmodules may be used by /sbin/hotplug or one of its agents (normally /etc/hotplug/usb.agent) when USB devices are "hot plugged" into the system.

Logical Volumes

dmsetup - low level logical volume management
dmsetup manages logical devices that use the device-mapper driver.

lvchange - change attributes of a logical volume
lvchange allows you to change the attributes of a logical volume including making them known to the kernel ready for use.

lvcreate - create a logical volume in an existing volume group
lvcreate creates a new logical volume in a volume group ( see vgcreate(8), vgchange(8) ) by allocating logical extents from the free physical extent pool of that volume group.

lvdisplay - display attributes of a logical volume
lvdisplay allows you to see the attributes of a logical volume like size, read/write status, snapshot information etc.

lvextend - extend the size of a logical volume
lvextend allows you to extend the size of a logical volume. Extension of snapshot logical volumes (see lvcreate(8) for information to create snapshots) is supported as well.

lvm - LVM2 tools
lvm provides the command-line tools for LVM2. A separate manual page describes each command in detail.

lvmchange - change attributes of the logical volume manager
lvmchange is not currently supported under LVM2, although dmsetup (8) has a remove_all command.

lvmdiskscan - scan for all devices visible to LVM2
vgscan scans all SCSI, (E)IDE disks, multiple devices and a bunch of other block devices in the system looking for LVM physical volumes. The size reported is the real device size. Define a filter in lvm.conf(5) to restrict the scan to avoid a CD ROM, for example.

lvreduce - reduce the size of a logical volume
lvreduce allows you to reduce the size of a logical volume. Be careful when reducing a logical volume's size, because data in the reduced part is lost!!!

lvremove - remove a logical volume
lvremove removes one or more logical volumes. Confirmation will be requested before deactivating any active logical volume prior to removal. Logical volumes cannot be deactivated or removed while they are open (e.g. if they contain a mounted filesystem).

lvrename - rename a logical volume
lvrename renames an existing logical volume from OldLogicalVolume{Name|Path} to NewLogicalVolume{Name|Path}.

lvresize - resize a logical volume
lvresize allows you to resize a logical volume. Be careful when reducing a logical volume's size, because data in the reduced part is lost!!!

lvs - report information about logical volumes
lvs produces formatted output about logical volumes.

lvscan - scan (all disks) for logical volumes
lvscan scans all known volume groups or all supported LVM block devices in the system for defined logical volumes.

pvchange - change attributes of a physical volume
pvchange allows you to change the allocation permissions of one or more physical volumes.

pvcreate - initialize a disk or partition for use by LVM
pvcreate initializes PhysicalVolume for later use by the Logical Volume Manager (LVM). Each PhysicalVolume can be a disk partition, whole disk, meta device, or loopback file.

pvdisplay - display attributes of a physical volume
pvdisplay allows you to see the attributes of one or more physical volumes like size, physical extent size, space used for the volume group descriptor area and so on.

pvmove - move physical extents
pvmove allows you to move the allocated physical extents (PEs) on SourcePhysicalVolume to one or more other physical volumes (PVs).

pvremove - remove a physical volume
pvremove wipes the label on a device so that LVM will no longer recognise it as a physical volume.

pvresize - resize a disk or partition in use by LVM2
pvresize resizes PhysicalVolume which may already be in a volume group and have active logical volumes allocated on it.

pvscan - scan all disks for physical volumes
pvscan scans all supported LVM block devices in the system for physical volumes.

vgcfgbackup - backup volume group descriptor area
vgcfgbackup allows you to backup the metadata of your volume groups. If you don't name any volume groups on the command line, all of them will be backed up.

vgcfgrestore - restore volume group descriptor area
vgcfgrestore allows you to restore the metadata of your volume groups from a text backup file produced by vgcfgbackup.

vgchange - change attributes of a volume group
vgchange allows you to change the attributes of one or more volume groups. Its main purpose is to activate and deactivate VolumeGroupName, or all volume groups if none is specified. Only active volume groups are subject to changes and allow access to their logical volumes.

vgck - check volume group metadata
vgck checks LVM metadata for each named volume group for consistency.

vgconvert - convert volume group metadata format
vgconvert converts VolumeGroupName metadata from one format to another provided that the metadata fits into the same space.

vgcreate - create a volume group
vgcreate creates a new volume group called VolumeGroupName using the block special device PhysicalVolumePath previously configured for LVM with pvcreate(8).

vgdisplay - display attributes of volume groups

vgdisplay allows you to see the attributes of VolumeGroupName (or all volume groups if none is given) with it's physical and  logical  volumes  and their sizes etc.

vgexport - make volume groups unknown to the system
vgexport allows you to make the inactive VolumeGroupName(s) unknown to the system. You can then move all the Physical Volumes in that Volume Group to a different system for later vgimport(8). Most LVM2 tools ignore exported Volume Groups.

vgextend - add physical volumes to a volume group
vgextend allows you to add one or more initialized physical volumes ( see pvcreate(8) ) to an existing volume group to extend it in size.

vgimport - make exported volume groups known to the system
vgimport allows you to make a Volume Group that was previously exported using vgexport(8) known to the system again, perhaps after moving its Physical Volumes from a different machine.

vgmerge - merge two volume groups
vgmerge merges two existing volume groups. The inactive SourceVolumeGroupName will be merged into the DestinationVolumeGroupName if physical extent sizes are equal and physical and logical volume summaries of both volume groups fit into DestinationVolumeGroupName's limits.

vgmknodes - recreate volume group directory and logical volume special files
Checks the LVM2 special files in /dev that are needed for active logical volumes and creates any missing ones and removes unused ones.

vgreduce - reduce a volume group
vgreduce allows you to remove one or more unused physical volumes from a volume group.

vgremove - remove a volume group
vgremove allows you to remove one or more volume groups.

vgrename - rename a volume group
vgrename renames an existing (see vgcreate(8) ) volume group.

vgs - report information about volume groups
vgs produces formatted output about volume groups.

vgscan - scan all disks for volume groups and rebuild caches
vgscan scans all SCSI, (E)IDE disks, multiple devices and a bunch of other disk devices in the system looking for LVM physical volumes and volume groups. Define a filter in lvm.conf(8) to restrict the scan to avoid a CD ROM, for example.

vgsplit - split a volume group into two
vgsplit creates NewVolumeGroupName and moves PhysicalVolumePath(s) from ExistingVolumeGroupName into it. Logical Volumes cannot be split between Volume Groups. Each existing Logical Volumes must be entirely on the Physical Volumes forming either the old or the new Volume Group.


arp - manipulate the system ARP cache
Arp manipulates the kernel's ARP cache in various ways. The primary options are clearing an address mapping entry and manually setting up one. For debugging purposes, the arp program also allows a complete dump of the ARP cache.

arping - send ARP REQUEST to a neighbour host
Ping destination on device interface by ARP packets, using source address source.

brctl - ethernet bridge administration
brctl is used to set up, maintain, and inspect the ethernet bridge configuration in the linux kernel.

dhclient - Dynamic Host Configuration Protocol Client
The Internet Systems Consortium DHCP Client, dhclient, provides a means for configuring one or more network interfaces using the Dynamic Host Configuration Protocol, BOOTP protocol, or if these protocols fail, by statically assigning an address.

dhcpcd - DHCP client daemon
dhcpcd is an implementation of the DHCP client specified in RFC2131 (when -r option is not specified) and RFC1541 (when -r option is specified). Support for draft-ietf-dhc-fqdn-option in use in many systems (particularly networks using Microsoft DHCP servers) is also provided.

ifconfig - configure a network interface
Ifconfig is used to configure the kernel-resident network interfaces. It is used at boot time to set up interfaces as necessary. After that, it is usually only needed when debugging or when system tuning is needed.

ip - show / manipulate routing, devices, policy routing and tunnels

mii-tool - view, manipulate media-independent interface status
This utility checks or sets the status of a network interface's Media Independent Interface (MII) unit. Most fast ethernet adapters use an MII to autonegotiate link speed and duplex setting.

nameif - name network interfaces based on MAC addresses
nameif renames network interfaces based on mac addresses.

rarp - manipulate the system RARP table
This program is obsolete. From version 2.3, the Linux kernel no longer contains RARP support.

route - show / manipulate the IP routing table
Route manipulates the kernel's IP routing tables. Its primary use is to set up static routes to specific hosts or networks via an interface after it has been configured with the ifconfig(8) program.

vconfig - VLAN (802.1q) configuration program.
The vconfig program allows you to create and remove vlan-devices on a vlan enabled kernel. Vlan-devices are virtual ethernet devices which represents the virtual lans on the physical lan.

Remote Filesystems

mount.cifs - mount using the Common Internet File System (CIFS)
This tool is part of the samba(7) suite.
mount.cifs mounts a Linux CIFS filesystem. It is usually invoked indirectly by the mount(8) command when using the "-t cifs" option. This command only works in Linux, and the kernel must support the cifs filesystem.

rpc.statd - NSM status monitor
The rpc.statd server implements the NSM (Network Status Monitor) RPC protocol. This service is somewhat misnamed, since it doesn't actually provide active monitoring as one might suspect; instead, NSM implements a reboot notification service. It is used by the NFS file locking service, rpc.lockd, to implement lock recovery when the NFS server machine crashes and reboots.

Security and Logging

accton - turn process accounting on or off
accton filename turns on process accounting. If called with no arguments, it will, by default, stop process accounting.

initlog - log messages and events to the system logger
initlog logs messages and events to the system logger. It is mainly designed for use in init scripts. initlog reads a configuration file /etc/initlog.conf by default, to determine its settings.

logsave - save the output of a command in a logfile
The logsave program will execute cmd_prog with the specified argument(s), and save a copy of its output to logfile. If the containing directory for logfile does not exist, logsave will accumulate the output in memory until it can be written out. A copy of the output will also be written to standard output.

pam_tally - The login counter (tallying) module
This module maintains a count of attempted accesses, can reset count on success, can deny access if too many attempts fail.

unix_chkpwd - helper binary that verifies the password of the current user
unix_chkpwd is a helper program for the pam_unix module that verifies the password of the current user. It is not intended to be run directly from the command line and logs a security violation if done so.

System Startup

bootlogd - record boot messages
Bootlogd runs in the background and copies all strings sent to the /dev/console device to a logfile. If the logfile is not accessible, the messages will be buffered in-memory until it is.

UPS Monitoring/Management

genpowerd - UPS monitor daemon
Genpowerd monitors the serial port connected to an UPS device and will perform an unattended shutdown of the system if the UPS is on battery longer than a specified number of minutes. Genpowerd needs to watch a tty with modem control properties, and [wiring details to be added.] Please refer to the genpowerd documentation for further information.

gentest - tests communication with UPS
Gentest monitors the serial port connected to a UPS and allows DTR and/or RTS lines to be stet to simulate the genpowerd UPS monitoring software.

User Administration

convertquota - convert quota from old file format to new one
convertquota converts old quota files quota.user and to files aquota.user and in new format currently used by 2.4.0-ac? and newer or by SuSE or Red Hat Linux 2.4 kernels on filesystem.

quotacheck - scan a filesystem for disk usage, create, check and repair quota files
quotacheck examines each filesystem, builds a table of current disk usage, and compares this table against that recorded in the disk quota file for the filesystem (this step is ommitted if option -c is specified). If any inconsistencies are detected, both the quota file and the current system copy of the incorrect quotas are updated (the latter only occurs if an active filesystem is checked which is not advised).

quotaon, quotaoff - turn filesystem quotas on and off
quotaon announces to the system that disk quotas should be enabled on one or more filesystems.

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