--- name: "lctl" section: "1" platform: "linux" package: "lustre-utils" version: "1.8.3-4" release: "Debian 6.0 (Squeeze)" platforms: ["linux"] url: "https://new.carta.tech/lctl" --- # lctl(1) Low level Lustre filesystem configuration utility ## NAME lctl - Low level Lustre filesystem configuration utility ## SYNOPSIS **lctl**\ **lctl --device \ \**\ ## DESCRIPTION **lctl** is used to directly control Lustre via an ioctl interface, allowing various configuration, maintenance, and debugging features to be accessed. **lctl** can be invoked in interactive mode by issuing lctl command. After that, commands are issued as below. The most common commands in lctl are **dl** , **device** , **network** *\* , **list\_nids** , **ping** *nid* , **help** , **quit.** To get a complete listing of available commands, type **help** at the lctl prompt. To get basic help on the meaning and syntax of a command, type **help** *command* Command completion is activated with the TAB key, and command history is available via the up- and down-arrow keys. For non-interactive use, one uses the second invocation, which runs command after connecting to the device. ### Network Configuration - **network** *\\|\* Start or stop LNET, or select a network type for other *lctl* LNET commands - **list\_nids** Print all Network Identifiers on the local node. LNET must be running. - **which\_nid** *\* From a list of nids for a remote node, show which interface communication will take place on. - **ping** *\* Check LNET connectivity via an LNET ping. This will use the fabric appropriate to the specified NID. - **interface\_list** Print the network interface information for a given **network** type. - **peer\_list** Print the known peers for a given **network** type. - **conn\_list** Print all the connected remote NIDs for a given **network** type. - **active\_tx** This command should print active transmits, and it is only used for elan network type. - **route\_list** Print the complete routing table. ### Device Selection - **device** *\* This will select the specified OBD device. All other commands depend on the device being set. - **device\_list** Show all the local Lustre OBDs. AKA **dl** ### Device Operations - **conf\_param** *\ \* Set a permanent configuration parameter for any device via the MGS. This command must be run on the MGS node. - **activate** Reactivate an import after deactivating, below. - **deactivate** Deactivate an import, in particular meaning do not assign new file stripes to an OSC. This command should be used on the OSC in the MDT LOV corresponding to a failed OST device, to prevent further attempts at communication with the failed OST. - **abort\_recovery** Abort the recovery process on a restarting MDT or OST device ### Virtual Block Device Operation Lustre is able to emulate a virtual block device upon regular file. It is necessary to be used when you are trying to setup a swap space via file. - **blockdev\_attach** *\ \* Attach the lustre regular file to a block device. If the device node is not existent, lctl will create it - it is recommended to create it by lctl since the emulator uses a dynamical major number. - **blockdev\_detach** *\* Detach the virtual block device. - **blockdev\_info** *\* Acquire which lustre file was attached to the device node. ### Debug - **debug\_daemon** Start and stop the debug daemon, and control the output filename and size. - **debug\_kernel** *\[file\] \[raw\]* Dump the kernel debug buffer to stdout or file. - **debug\_file** *\ \[output\]* Convert kernel-dumped debug log from binary to plain text format. - **clear** Clear the kernel debug buffer. - **mark** *\* Insert marker text in the kernel debug buffer. - **filter** *\* Filter kernel debug messages by subsystem or mask. - **show** *\* Show specific type of messages. - **debug\_list** *\* List all the subsystem and debug types. - **modules** *\* Provide gdb-friendly module information. ## OPTIONS The following options can be used to invoke lctl. - **--device** The device to be used for the operation. This can be specified by name or number. See **device\_list** - **--ignore\_errors \| ignore\_errors** Ignore errors during script processing - \# lctl ## EXAMPLES lctl \> dl\ 0 UP mgc MGC192.168.0.20@tcp bfbb24e3-7deb-2ffa-eab0-44dffe00f692 5\ 1 UP ost OSS OSS\_uuid 3\ 2 UP obdfilter testfs-OST0000 testfs-OST0000\_UUID 3\ lctl \> dk /tmp/log Debug log: 87 lines, 87 kept, 0 dropped.\ lctl \> quit \# lctl conf\_param testfs-MDT0000 sys.timeout=40 ## BUGS Please report all bugs to Sun Microsystems, Inc. http://bugzilla.lustre.org/ ## AVAILABILITY **lctl** is part of the **Lustre**(7) filesystem package and is available from Sun Microsystems, Inc.\ http://www.sun.com/software/products/lustre/index.xml ## SEE ALSO **Lustre**(7), [**mkfs.lustre**(8)](/mkfs.lustre/8.md), [**mount.lustre**(8)](/mount.lustre/8.md), **lctl**(8), **lfs**(1)