TGTADM(8) [FIXME: manual] TGTADM(8) NAME tgtadm - Linux SCSI Target Administration Utility SYNOPSIS tgtadm [OPTIONS]... [-C --control-port ] [-L --lld ] [-o --op ] [-m --mode ] [-t --tid ] [-T --targetname ] [-y --blocksize ] [-Y --device-type ] [-l --lun ] [-b --backing-store ] [-f --bsoflags {direct|sync}] [-S --bsopts {backing-store opt string}] [-E --bstype ] [-I --initiator-address
] [-Q --initiator-name ] [-n --name ] [-v --value ] [-P --params ] [-F --force] [-h --help] DESCRIPTION tgtadm is used to monitor and modify everything about Linux SCSI target software: targets, volumes, etc. OPTIONS -C, --control-port It is possible to run multiple concurrent instances of tgtd on a host. This argument is used to control which instance the tgtadm command will operate on. -y, --blocksize Block devices are created with a default block size of 512 bytes. This argument can be used to create block devices with different block sizes. Example: tgtadm --lld iscsi --mode logicalunit --op new \ --tid --lun \ -b --blocksize=4096 -Y, --device-type When creating a LUN, this parameter specifies the type of device to create. Default is disk. Possible device-types are: disk : emulate a disk device tape : emulate a tape reader ssc : same as tape cd : emulate a DVD drive changer : emulate a media changer device pt : passthrough type to export a /dev/sg device -E, --bstype When creating a LUN, this parameter specifies the type of backend storage to to use. Possible backend types are: rdwr : Use normal file I/O. This is the default for disk devices aio : Use Asynchronous I/O rbd : Use Ceph's distributed-storage RADOS Block Device sg : Special backend type for passthrough devices ssc : Special backend type for tape emulation --lld --op new --mode target --tid --targetname Add a new target with and . --lld --op delete --mode target --tid Delete specific target with . The target must have no active I_T nexus. --lld --op delete --force --mode target --tid Delete specific target forcibly with . --lld --op show --mode target Show all the targets. --lld --op show --mode target --tid Show target parameters of a target with . --lld --op new --mode logicalunit --tid --lun --backing-store --bsopts= Add a new logical unit with to specific target with . The logical unit is offered to the initiators. must be block device files (including LVM and RAID devices) or regular files, or an RBD image or snapshot name for --bstype rbd. lun0 is reserved for a special device automatically created. Example: If tgt is compiled with the bs_rbd backing store for Ceph RBD images (see tgtadm --mode system --op show to verify), set up a target mapping the rbd image named "rbdimage", and pass options to bs_rbd: tgtadm --lld iscsi --op new --mode logicalunit --tid 1 \ --lun 1 --bstype=rbd --backing-store=rbdimage \ --bsopts="conf=/etc/ceph/ceph.conf;id=tgt" --lld --op delete --mode logicalunit --tid --lun Delete specific logical unit with that the target with has. --lld --op bind --mode target --tid --initiator-address
Add the address to the access lists of the target with . Initiators with the address can access to the target. 'ALL' is a special address to allow all initiators to access to a target. --lld --op bind --mode target --tid --initiator-name Add the initiator's name to the access lists of the target with . Initiators with the names can access to the target. --lld --op unbind --mode target --tid --initiator-address
Delete the address from the access lists of the target with . --lld --op unbind --mode target --tid --initiator-name Delete the initiator's name from the access lists of the target with . --lld --op update --mode target --tid --name= --value= Change the value of of the target with to . --lld --op update --mode target --tid --params parameter=value<,...> Sets/changes the value of one or more target parameters. --lld --op update --mode logicalunit --tid --lun --params parameter=value<,...> Sets/changes the value of one or more logical unit parameters. --lld --op start --mode lld Start the specified lld without restarting the tgtd process. Can be used to initialize lld driver in case required modules were loaded after tgtd was already executed. --help Display a list of available options and exits. LUN PARAMETERS These parameters are only applicable for "--mode logicalunit". vendor_id= This parameter sets the Vendor Identification string that a LUN will report in INQURY data. product_id= This parameter sets the Product Identification string that a LUN will report in INQURY data. product_rev= This parameter sets the Product Revision string that a LUN will report in INQURY data. Example: tgtadm --lld iscsi --mode logicalunit --op update \ --tid --lun \ --params vendor_id=TGTD,product_id=VirtualHD,product_rev=0103 removable=<0|1> This can be used to override/change the default setting for the removable flag. Disk devices default to non-removable while DVD and TAPE devices default to removable. sense_format=<0|1> This flag controls the format of sense data that the device will return. 0 = Clasic sense format, 1 = Support descriptor format. online=<0|1> This controls whether a device is online or not. Devices default to be online when created but can be brought offline using this parameter. Behaviour of offline devices depend on device type. An MMC/DVD device that is offline will report that there is no disk in the unit but the actual MMC/DVD unit itself can still be communicated with. All other device types will fail all I/O with a sense code of Not Ready. Example: tgtadm --lld iscsi --mode logicalunit --op update \ --tid 1 --lun 1 \ --params removable=1,sense_format=1,online=1 mode_page= This parameter is used to set specific mode pages for the device and the mode page contents. Most devices default to reasonable default mode pages automatically when the LUN is created, but this allows special settings. Examples: Create mode page '2', subpage 0 and 14 bytes of data. This is Disconnect-Reconnect mode page. tgtadm --mode logicalunit --op update --tid 1 --lun 2 \ --params mode_page=2:0:14:0x80:0x80:0:0xa:0:0:0:0:0:0:0:0:0:0 Create mode page '10', subpage 0 and 10 bytes of data. This is Control Extension mode page. tgtadm --lld iscsi --mode logicalunit --op update --tid 1 --lun 2 \ --params mode_page=10:0:10:2:0:0:0:0:0:0:0:2:0 Create mode page '0x1c', subpage 0 and 10 bytes of data. This is Informational Exceptions Control mode page. tgtadm --lld iscsi --mode logicalunit --op update --tid 1 --lun 2 \ --params mode_page=0x1c:0:10:8:0:0:0:0:0:0:0:0:0 readonly=<0|1> This sets the read-only flag of a LUN. A read-only LUN will refuse any attempts to write data to it. This parameter only applies to DISK devices. tgtadm --lld iscsi --mode logicalunit --op update --tid 1 --lun 1 \ --params readonly=1 thin_provisioning=<0|1> This controls the provisioning for the LUN. A thin-provisioned LUN is represented as a sparse file. TGTD supports provisioning type 2 for sparse files. When initiators use the SCSI UNMAP command TGTD will release the affected areas back to the filesystem using FALLOC_FL_PUNCH_HOLE. This parameter only applies to DISK devices. Thin-provisioning works for LUNs stored on filesystems that support FALLOC_FL_PUNCH_HOLE. When using thin-provisioning option with a block device such a SSD or ZVOL, UNMAP SCSI command discards the region from the block device. tgtadm --lld iscsi --mode logicalunit --op update --tid 1 --lun 1 \ --params thin_provisioning=1 rotation_rate= This sets the reported rotation rate in RPM of the LUN to the initiator. Some operating systems assume a SSD type disk when this parameter is zero. This parameter only applies to DISK devices. tgtadm --lld iscsi --mode logicalunit --op update --tid 1 --lun 1 \ --params rotation_rate=0 SMC SPECIFIC LUN PARAMETERS These parameters are only applicable for luns that are of type "changer" i.e. the media changer device for a DVD Jukebox or a Virtual Tape Library. element_type=<1|2|3|4> This controls which type of element a certain slot in the jukebox/vtl is. Slot types: 1 -> Medium Transport (picker arm) 2 -> Storage Element 3 -> Import/Export Element 4 -> Data Transfer device (CD drive, tape drive, MO drive etc) address=<1-65535> This is used to create/operate on a single slot. Address specifies the slot on which to perform the operation. start_address=<1-65535>,quantity=<1--65535> This is used to create/operate on an entire range of slots at once. Start_address specifies the first address to operate on and quantity specifies the number of consequtive slots. sides=<1|2> When creating storage elements, i.e. "element_type=2", this parameter specifies if the media has 1 or two sides to hold data. clear_slot=<1> This option is used to clear a storage element and remove any media that may be present. Once this command completes the storage element will show up as "Empty". barcode= This is used to assign a barcode to an element. Barcodes are limited to 10 characters in tgtd. volume_tag= This is used to assign a volume tag to SMC storage elements. If no volume tag is specified tgtd will use fall back to the barcode. The volume tag can be up to 32 characters. media_home= This parameter specifies a directory where all virtual media for the dvd/tape device elements are stored. To assign a media image file to a storage element slot, you assign "barcode" to be the name of the image file in the "media_home" directory. Example: How to create a DVD jukebox with eight disk trays and two empty DVD-R disks. # Create a target tgtadm --lld iscsi --mode target --op new --tid 1 --targetname iqn.2007-03:virtual-dvd:`hostname` # Create a DVD drive and give it a nice name # The dvd starts out without a backing store file, i.e. no disk loaded tgtadm --op new --mode logicalunit --tid 1 --lun 1 --device-type cd tgtadm --lld iscsi --mode logicalunit --op update --tid 1 --lun 1 --params vendor_id=STGT_DVD,product_id=DVD101,product_rev=0010,scsi_sn=STGTDVD01,removable=1 # We need a backend store file for the media changer if [ ! -f $HOME/smc ]; then dd if=/dev/zero of=$HOME/smc bs=1k count=1 fi # Create the SMC device and give it a nice name tgtadm --lld iscsi --mode logicalunit --op new --tid 1 --lun 2 --backing-store $HOME/smc --device-type changer tgtadm --lld iscsi --mode logicalunit --op update --tid 1 --lun 2 --params vendor_id=STK,product_id=L700,product_rev=0010,scsi_sn=XYZZY_0,removable=1 # Add a Data Transfer devices (1 drive) tgtadm --lld iscsi --mode logicalunit --op update --tid 1 --lun 2 --params element_type=4,start_address=1,quantity=1 # Specify that the DVD above (LUN 1) is the data transfer device we created tgtadm --lld iscsi --mode logicalunit --op update --tid 1 --lun 2 --params element_type=4,address=1,tid=1,lun=1 # Medium Transport Elements (robot arm / picker) tgtadm --lld iscsi --mode logicalunit --op update --tid 1 --lun 2 --params element_type=1,start_address=16,quantity=1 # define path to virtual media VTL=${HOME}/vtl mkdir -p ${VTL} tgtadm --lld iscsi --mode logicalunit --op update --tid 1 --lun 2 --params media_home=${VTL} # Storage Elements - 8 starting at addr 1024 tgtadm --lld iscsi --mode logicalunit --op update --tid 1 --lun 2 --params element_type=2,start_address=1024,quantity=8 # Add 'media' to slots 1 and 2 and leave the other 6 slots empty # slot 1 # Create empty writeable virtual DVD-R media tgtimg --op new --device-type cd --type dvd+r --file ${VTL}/DISK_001 tgtadm --lld iscsi --mode logicalunit --op update --tid 1 --lun 2 --params element_type=2,address=1024,barcode=DISK_001,volume_tag="A blank disk",sides=1 # slot 2 tgtimg --op new --device-type cd --type dvd+r --file ${VTL}/DISK_002 tgtadm --lld iscsi --mode logicalunit --op update --tid 1 --lun 2 --params element_type=2,address=1025,barcode=DISK_002,volume_tag="My second blank disk",sides=1 # Allow ALL initiators to connect to this target tgtadm --lld iscsi --mode target --op bind --tid 1 --initiator-address ALL # Show all our good work. tgtadm --lld iscsi --mode target --op show PASSTHROUGH DEVICES In addition to device emulation TGTD also supports utilizing existing SG devices on the host and exporting these through a special passthrough device type. --bstype=sg This specifies that an SG devices is used. --device-type=pt This specifies that passthrough device type is used. --backing-store= This specifies which device to export through TGTD. --bsoflags={direct|sync} This argument is used when creating a LUN to specify extra flags to use when opening the backing file. O_DIRECT is specified by "direct" and O_SYNC by "sync". Example: Make /dev/sg4 available to initiators connecting to TGTD. tgtadm --lld iscsi --op new --mode logicalunit --tid 1 --lun 1 --bstype=sg --device-type=pt --backing-store=/dev/sg4 Example: Open the backing file with O_SYNC. tgtadm --lld iscsi --op new --mode logicalunit --tid 1 --lun 1 --bsoflags="sync" --backing-store=/data/100m_image.raw HEADER DIGEST AND DATA DIGEST Header and data digests can be set on a per target parameter. TGTD supports two modes, None and CRC32C. When the digest is set to None, TDTD will negotiate that digests will not be used, and when CRC32C is set, TGTD will force the connection to use digest. Viewing the current settings This command is used to view the current settings for header/data digest. tgtadm --op show --mode target --tid 1 ... HeaderDigest=None DataDigest=None ... Setting digest Set header digest to CRC32C: tgtadm --op update --mode target --tid 1 -n HeaderDigest -v CRC32C Set data digest to None: tgtadm --op update --mode target --tid 1 -n DataDigest -v None CHAP AUTHENTICATION CHAP authentication is supported to require authentication before an initiator is allowed to log in and access devices. CHAP main-phase authentication is set on the target level. To set up CHAP authentication we first need to create an account and its associated password, then we bind the account to one or more targets. Setting CHAP on a target These two commands create a user account and binds it to target 1. tgtadm --lld iscsi --op new --mode account --user ronnie --password password tgtadm --lld iscsi --op bind --mode account --tid 1 --user ronnie List all accounts This command is used to list all accounts that have been created. tgtadm --lld iscsi --op show --mode account Account list: ronnie Show if a target requires authentication When listing the targets, each target that has authantication enabled will contain a listing of all accoutns bound to that target. tgtadm --lld iscsi --op show --mode target Target 1: iqn.ronnie.test ... Account information: ronnie ... NOP-OUT PROBES TGTD can send NOP-OUT probes to connected initiators to determine when an initiator is dead and then automatically clear and tear down the TCP connection. This can either be set as a global default from the tgtd command-line or it can be set for individual targets using the tgtadm command. Check the current NOP-OUT setting The tgtadm command is used to view the current setting for if/when to send NOP-OUT probes to connected initiators. If the target is configured to send NOP-OUT probes this will show up as two parameter lines in the target printout. If the target is not configured to send NOP-OUT these lines will not be printed at all. tgtadm --lld iscsi --op show --mode target Target 1: iqn.ronnie.test System information: Driver: iscsi State: ready Nop interval: 5 Nop count: 5 I_T nexus information: Setting NOP-OUT for a target The tgtadm command is used to change the NOP-OUT settings. tgtadm --op update --mode target --tid 1 -n nop_count -v 5 tgtadm --op update --mode target --tid 1 -n nop_interval -v 5 ISCSI PORTALS iSCSI portals can be viewed, added and removed at runtime. List portals This command is used to list the current iSCSI portals defined on the target: tgtadm --lld iscsi --op show --mode portal Portal: 10.1.1.101:3260,1 Portal: 127.0.0.1:3260,1 Add portal This command is used to add a portal to the target : tgtadm --lld iscsi --op new --mode portal --param portal=10.1.1.101:3260 Remove portal This command is used to remove a portal from the target : tgtadm --lld iscsi --op delete --mode portal --param portal=10.1.1.101:3260 ISCSI CONNECTIONS iSCSI connections can be viewed and forced closed at runtime. List all active connections for a target This command is used to list the all the active iSCSI connections to the target with connection id, initiator name and ip address for the initiator : tgtadm --lld iscsi --op show --mode conn --tid 1 Session: 2 Connection: 0 Initiator: iqn.2008-11.org.linux-kvm: IP Address: 127.0.0.1 Close an existing connection This command is used to close an iSCSI connection. Note that forcibly closing iSCSI connections can lead to data-loss. tgtadm --lld iscsi --op delete --mode conn --tid 1 --sid 2 --cid 0 ONLINE/OFFLINE STATUS Tgtd LUNs can be in online or offline status. LUNs that are Offline behave slightly different depending on the device type. Offline devices behave as if there is no media available and any operations that access media will fail with an check-condition error. Devices can not be set to Offline mode while there are "PREVENT ALLOW MEDIUM REMOVAL" locks on the device. Similarly media in Online devices can not be software ejected while there are such locks on the device (the 'eject' command will fail). Show Online/Offline status Finding the Online/Offline status of a LUN is done through the tgtd command. If "Prevent removal" is "Yes" this indicates that an application holds a "prevent media removal" lock on the device. tgtadm --lld iscsi --mode target --op show ... LUN: 2 Type: cd/dvd SCSI ID: IET 00010002 SCSI SN: beaf12 Size: 3432 MB, Block size: 1 Online: Yes Removable media: Yes Prevent removal: Yes ... Changing a LUN to Offline A LUN is changed to Offline status using the tgtadm command. When devices are set Offline these devices will behave as if there is no media loaded into the drive. Change a LUN to become offline. (no disk in the drive) tgtadm --tid 1 --lun 2 --op update --mode logicalunit -P Online=No ISNS PARAMETERS iSNS configuration for a target is by using the tgtadm command. iSNSServerIP This specifies the IP address of the iSNS server. TGTD only supprots one iSNS server. Example: tgtadm --op update --mode sys --name iSNSServerIP --value 192.168.11.133 iSNS This setting enables(on)/disables(off) iSNS. Example: tgtadm --op update --mode sys --name iSNS --value On iSNSServerPort This setting specifies the port to use for iSNS. Example: tgtadm --op update --mode sys --name iSNSServerPort --value 3205 iSNSAccessControl Enable/disable access control for iSNS. Example: tgtadm --op update --mode sys --name iSNSAccessControl --value Off SEE ALSO tgtd(8), tgt-admin(8), tgtimg(8), tgt-setup-lun(8). https://github.com/fujita/tgt REPORTING BUGS Report bugs to [FIXME: source] 09/05/2024 TGTADM(8)