--- name: "nvmecontrol" section: "8" platform: "freebsd" package: "base" version: "16.0-CURRENT-20261027-61c70dc16a79" release: "FreeBSD 16.0-CURRENT (2026-10-27)" platforms: ["freebsd"] url: "https://new.carta.tech/nvmecontrol" --- # nvmecontrol(8) NVM Express control utility ## NAME **nvmecontrol** – NVM Express control utility ## SYNOPSIS **nvmecontrol** **devlist** \[**-h**\] **nvmecontrol** **identify** \[**-v**\] \[**-x**\] \[**-n** *nsid*\] ⟨*device-id* \| *namespace-id*⟩ **nvmecontrol** **perftest** ⟨**-n** *num\_threads*⟩ ⟨**-o** *read\|write*⟩ \[**-p**\] ⟨**-s** *size\_in\_bytes*⟩ ⟨**-t** *time\_in\_sec*⟩ ⟨*namespace-id*⟩ **nvmecontrol** **reset** ⟨*device-id*⟩ **nvmecontrol** **logpage** ⟨**-p** *page\_id*⟩ \[**-x**\] \[**-v** *vendor-string*\] \[**-b**\] \[**-f** *LSP*\] \[**-i** *LSI*\] \[**-r**\] ⟨*device-id* \| *namespace-id*⟩ **nvmecontrol** **ns** **active** ⟨*device-id*⟩ **nvmecontrol** **ns** **allocated** ⟨*device-id*⟩ **nvmecontrol** **ns** **attach** ⟨**-n** *nsid*⟩ ⟨**-c** *cntid*⟩ ⟨*device-id*⟩ **nvmecontrol** **ns** **attached** ⟨**-n** *nsid*⟩ ⟨*device-id*⟩ **nvmecontrol** **ns** **controllers** ⟨*device-id*⟩ **nvmecontrol** **ns** **create** ⟨**-s** *nsze*⟩ \[**-c** *ncap*\] \[**-f** *lbaf*\] \[**-m** *mset*\] \[**-n** *nmic*\] \[**-p** *pi*\] \[**-l** *pil*\] \[**-L** *flbas*\] \[**-d** *dps*\] ⟨*device-id*⟩ **nvmecontrol** **ns** **delete** ⟨**-n** *nsid*⟩ ⟨*device-id*⟩ **nvmecontrol** **ns** **detach** ⟨**-n** *nsid*⟩ ⟨**-c** *cntid*⟩ ⟨*device-id*⟩ **nvmecontrol** **ns** **identify** \[**-v**\] \[**-x**\] ⟨**-n** *nsid*⟩ ⟨*device-id*⟩ **nvmecontrol** **nsid** ⟨*device-id* \| *namespace-id*⟩ **nvmecontrol** **resv** **acquire** ⟨**-c** *crkey*⟩ \[**-p** *prkey*\] ⟨**-t** *rtype*⟩ ⟨**-a** *racqa*⟩ ⟨*namespace-id*⟩ **nvmecontrol** **resv** **register** \[**-i**\] \[**-c** *crkey*\] ⟨**-k** *nrkey*⟩ ⟨**-r** *rrega*⟩ \[**-p** *cptpl*\] ⟨*namespace-id*⟩ **nvmecontrol** **resv** **release** ⟨**-c** *crkey*⟩ ⟨**-t** *rtype*⟩ ⟨**-a** *rrela*⟩ ⟨*namespace-id*⟩ **nvmecontrol** **resv** **report** \[**-e**\] \[**-v**\] \[**-x**\] ⟨*namespace-id*⟩ **nvmecontrol** **firmware** \[**-s** *slot*\] \[**-f** *path\_to\_firmware*\] \[**-a**\] ⟨*device-id*⟩ **nvmecontrol** **format** \[**-n**\] \[**-f** *fmt*\] \[**-s** *sector-size*\] \[**-m** *mset*\] \[**-p** *pi*\] \[**-l** *pil*\] \[**-E**\] \[**-C**\] ⟨*device-id* \| *namespace-id*⟩ **nvmecontrol** **sanitize** ⟨**-a** *sanact*⟩ \[**-c** *owpass*\] \[**-d**\] \[**-p** *ovrpat*\] \[**-r**\] \[**-I**\] \[**-U**\] ⟨*device-id*⟩ **nvmecontrol** **power** \[**-a** *apst\_state*\] \[**-d** *apst\_data*\] \[**-l**\] \[**-m** *apst\_limit*\] \[**-p** **-power\_state**\] \[**-w** **-workload\_hint**\] ⟨*device-id* \| *namespace-id*⟩ **nvmecontrol** **selftest** ⟨**-c** *code*⟩ ⟨*device-id* \| *namespace-id*⟩ **nvmecontrol** **wdc** **cap-diag** \[**-o** **-path\_template**\] ⟨*device-id*⟩ **nvmecontrol** **wdc** **drive-log** \[**-o** **-path\_template**\] ⟨*device-id*⟩ **nvmecontrol** **wdc** **get-crash-dump** \[**-o** **-path\_template**\] ⟨*device-id*⟩ **nvmecontrol** **admin-passthru** \[args\] ⟨*device-id*⟩ **nvmecontrol** **io-passthru** \[args\] ⟨*namespace-id*⟩ **nvmecontrol** **discover** \[**-v**\] \[**-t** *transport*\] \[**-q** *HostNQN*\] **nvmecontrol** **connect** \[**-FGg**\] \[**-c** *cntl-id*\] \[**-i** *queues*\] \[**-k** *seconds*\] \[**-l** *seconds*\] \[**-r** *seconds*\] \[**-t** *transport*\] \[**-q** *HostNQN*\] \[**-Q** *entries*\] ⟨*address*⟩ ⟨*SubNQN*⟩ **nvmecontrol** **connect-all** \[**-FGg**\] \[**-i** *queues*\] \[**-k** *seconds*\] \[**-l** *seconds*\] \[**-r** *seconds*\] \[**-t** *transport*\] \[**-q** *HostNQN*\] \[**-Q** *entries*\] ⟨*address*⟩ **nvmecontrol** **disconnect** ⟨*device-id* \| *namespace-id* \| *SubNQN*⟩ **nvmecontrol** **reconnect** ⟨*device-id*⟩ **nvmecontrol** **reconnect** \[**-FGg**\] \[**-i** *queues*\] \[**-k** *seconds*\] \[**-l** *seconds*\] \[**-r** *seconds*\] \[**-t** *transport*\] \[**-q** *HostNQN*\] \[**-Q** *entries*\] ⟨*device-id*⟩ ⟨*address*⟩ **nvmecontrol** **telemetry-log** **-O** *output-file* \[**-d** *data-area*\] \[**-v**\] ⟨*device-id*⟩ ## DESCRIPTION NVM Express (NVMe) is a storage protocol standard for SSDs and other high-speed storage devices over PCI Express as well as remote storage devices accessed via a network fabric. ### devlist List all NVMe controllers and namespaces along with their device nodes. With the **-h** argument, use unit suffixes: Byte, Kibibyte, Mebibyte, Gibibyte, Tebibyte and Pebibyte (based on powers of 1024) when showing the disk space. By default, uses Mebibyte. ### identify The identify commands reports information from the drive's IDENTIFY\_CONTROLLER if a *device-id* is specified. It reports IDENTIFY\_NAMESPACE data if a *namespace-id* is specified. When used with disk names, the IDENTIFY\_NAMESPACE data is reported, unless the namespace *nsid* is overridden with the **-n** flag. Then that namespace's data is reported, if it exists. The command accepts the following parameters: - **-n** The namespace ⟨nsid⟩ to use instead of the namespace associated with the device. A *nsid* of “0” is used to retrieve the IDENTIFY\_CONTROLLER data associated with that drive. ### logpage The logpage command knows how to print log pages of various types. It also knows about vendor specific log pages from HGST/WDC, Samsung, Micron and Intel. Note that some vendors use the same log page numbers for different data. - Page 0x01 Drive Error Log - Page 0x02 Health/SMART Data - Page 0x03 Firmware Information - Page 0x04 Changed Namespace List - Page 0x05 Commands Supported and Effects - Page 0x06 Device Self-test - Page 0x80 Reservation Notification - Page 0x81 Sanitize Status - Page 0xc1 Advanced SMART information (WDC/HGST) - Page 0xc1 Read latency stats (Intel) - Page 0xc2 Write latency stats (Intel) - Page 0xc5 Temperature stats (Intel) - Page 0xca Advanced SMART information (Intel) - Page 0xca Extended SMART information (Samsung) - Page 0xca Vendor Unique SMART information (Micron) Specifying **-v** **help** will list all valid vendors and pages. **-x** will print the page as hex. **-b** will print the binary data for the page. **-s** will set Log Specific Field. **-i** will set Log Specific Identifier. **-r** will set Retain Asynchronous Event. ### ns Various namespace management commands. If namespace management is supported by device, allow list, create and delete namespaces, list, attach and detach controllers to namespaces. Each NVM device consists of one or more NVM subsystems. Each NVM subsystem has one or more NVM ports. Each NVM port is attached to one or more NVM controllers (though typically 1). Each NVM controller is attached to one or more namespaces. After a namespace is created, it is considered “allocated”. All namespaces that have not been created are unallocated. An allocated namespace may be active or inactive. An active namespace is attached to the controller and may be interacted with. A namespace can move from active to inactive when detached. An allocated namespace may be deleted to become unallocated. For more details on the nuances of NVM namespaces, please see section 2 *Theory* *of* *Operation* and section 3 *NVM* *Express* *Architecture* of the latest NVM standard. ### ns active Provide a list of active namespace identifiers for the given NVM controller. ### ns allocated Provide a list of allocated namespace identifiers for the given NVM controller. ### ns attach Attach an nsid to a controller. The primary controller is used if one is not specified. ### ns attached Provide a list of controllers attached to a nsid. If only a nvme controller argument is provided, a nsid must also be specified. ### ns controllers Provide a list of all controllers in the NVM subsystem. ### ns create Creates a new namespace. ### ns delete Delete a namespace. It must be currently inactive. ### ns detach Detach a namespace from a controller. The namespace will become inaccessible, but its contents will remain if it is *activated* again. ### ns identify Print detailed information about the namespace. ### nsid Reports the namespace id and controller device associated with the ⟨*namespace-id*⟩ or ⟨*device-id*⟩ argument. ### resv acquire Acquire or preempt namespace reservation, using specified parameters: - **-a** Acquire action: - 0 Acquire - 1 Preempt - 2 Preempt and abort - **-c** Current reservation key. - **-p** Preempt reservation key. - **-t** Reservation type: - 1 Write Exclusive - 2 Exclusive Access - 3 Write Exclusive - Registrants Only - 4 Exclusive Access - Registrants Only - 5 Write Exclusive - All Registrants - 6 Exclusive Access - All Registrants ### resv register Register, unregister or replace reservation key, using specified parameters: - **-c** Current reservation key. - **-k** New reservation key. - **-r** Register action: - 0 Register - 1 Unregister - 2 Replace - **-i** Ignore Existing Key - **-p** Change Persist Through Power Loss State: - 0 No change to PTPL state - 2 Set PTPL state to 0. Reservations are released and registrants are cleared on a power on. - 3 Set PTPL state to 1. Reservations and registrants persist across a power loss. ### resv release Release or clear reservation, using specified parameters: - **-c** Current reservation key. - **-t** Reservation type. - **-a** Release action: - 0 Release - 1 Clean ### resv report Print reservation status, using specified parameters: - **-x** Print reservation status in hex. - **-e** Use Extended Data Structure. ### format Format either specified namespace, or all namespaces of specified controller, using specified parameters: - **-n**, **-****-dry-run** Print the resolved Format NVM command without submitting it to the controller. Identify commands needed to resolve and validate the format parameters are still performed. - **-f** *fmt* The index *fmt* of the parameters to use. LBA Format #, as specified in the identification of the namespace using “nvmecontrol identify” command with a namespace specified maps this index into these parameters. - **-s** *sector-size* Select the LBA format matching the specified total sector size. The data size is the largest power of two not greater than *sector-size*, and any remainder is the metadata size. When formatting a namespace, the format with the best relative performance is selected, with the lowest format index used to break ties. When formatting a controller, every active namespace must have exactly one matching format, and that format must have the same index in every namespace. The effective *mset*, *pi*, and *pil* values must also match across all active namespaces. Otherwise, the operation is rejected. This option is mutually exclusive with **-f**. - **-m** *mset* Metadata Setting. *mset* - 0 do not transfer metadata with LBA information - 1 Transfer the metadata as part of the extended LBA information. - **-p** *pi* Protection Information. - 0 Protection Information not enabled. - 1 Type 1 information protection enabled. - 2 Type 2 information protection enabled. - 3 Type 3 information protection enabled. - **-l** *pil* Protection Information Location. - 0 Transfer the protection metadata as the last N bytes of the transfer. - 1 Transfer the protection metadata as the first N bytes of the transfer. - **-E** Enables User Data Erase during format. All users data is erased and subsequent reads are indeterminate. The drive may implement this as a cryptographic erase or it may physically erase the underlying media. - **-C** Enables Cryptographic Erase during format. All user data is erased cryptographically by deleting the encryption key, rendering it unintelligible. When formatting specific namespace, existing values are used as defaults. When formatting all namespaces, all parameters should be specified. Some controllers may not support formatting or erasing specific or all namespaces. The [nvme(4)](/nvme/4.md) driver does not currently support metadata and protection information transfers. ### sanitize Sanitize NVM subsystem of specified controller, using specified parameters: - **-a** *operation* Specify the sanitize operation to perform. - overwrite Perform an overwrite operation by writing a user supplied data pattern to the device one or more times. The pattern is given by the **-p** argument. The number of times is given by the **-c** argument. - block Perform a block erase operation. All the device's blocks are set to a vendor defined value, typically zero. - crypto Perform a cryptographic erase operation. The encryption keys are changed to prevent the decryption of the data. - exitfailure Exits a previously failed sanitize operation. A failed sanitize operation can only be exited if it was run in the unrestricted completion mode, as provided by the **-U** argument. - 1, 2, 3, 4 nvme-cli compatible **-a** values for “exitfailure”, “block”, “overwrite”, and “crypto” respectively. - **-c** *passes* The number of passes when performing an ‘overwrite’ operation. Valid values are between 1 and 16. The default is 1. - **-d** No Deallocate After Sanitize. - **-I** When performing an ‘overwrite’ operation, the pattern is inverted between consecutive passes. - **-p** *pattern* 32 bits of pattern to use when performing an ‘overwrite’ operation. The pattern is repeated as needed to fill each block. - **-U** Perform the sanitize in the unrestricted completion mode. If the operation fails, it can later be exited with the ‘exitfailure’ operation. - **-r** Run in “report only” mode. This will report status on a sanitize that is already running on the drive. ### power Manage the power modes of the NVMe controller. - **-a** *state* Enable (1) or disable (0) Autonomous Power State Transition (APST). When enabled, the controller will autonomously switch power states according to configuration data. - **-d** *target:idle\[,target:idle* *...\]* Set the APST data. Each target:idle pair corresponds to a specific available power state starting from the lowest, and defines the target state to transition to, as well as the idle time in milliseconds to wait before that transition. Setting both parameters to zero disables switching from that state. - **-l** List all supported power modes. Modes marked with an asterisk (“\*”) are non-operational power modes. - **-m** *limit* Configure APST to use all available non-operational power states with total latency below the specified *limit* (in milliseconds). - **-p** *mode* Set the power mode to *mode*. This must be a mode listed with the ``` nvmecontrol power -l ``` command. - **-w** *hint* Set the workload hint for automatic power mode control. - 0 No workload hint is provided. - 1 Extended idle period workload. The device is often idle for minutes at a time. A burst of write commands comes in over a period of seconds. Then the device returns to being idle. - 2 Heavy sequential writes. A huge number of sequential writes will be submitted, filling the submission queues. - Other All other values are reserved and have no standard meaning. Please see the “NVM Subsystem Workloads” section of the relevant NVM Express Base Standard for details. ### selftest Start the specified device self-test: - **-c** *code* Specify the device self-test command code. Common codes are: - 0x1 Start a short device self-test operation - 0x2 Start an extended device self-test operation - 0xe Start a vendor specific device self-test operation - 0xf Abort the device self-test operation ### wdc The various wdc command retrieve log data from the wdc/hgst drives. The **-o** flag specifies a path template to use to output the files. Each file takes the path template (which defaults to nothing), appends the drive's serial number and the type of dump it is followed by .bin. These logs must be sent to the vendor for analysis. This tool only provides a way to extract them. ### passthru The “admin-passthru” and “io-passthru” commands send NVMe commands to either the administrative or the data part of the device. These commands are expected to be compatible with nvme-cli. Please see the NVM Express Base Standard for details. - **-o** **--opcode** *opcode* Opcode to send. - **-2** **--cdw2** *value* 32-bit value for CDW2. - **-3** **--cdw3** *value* 32-bit value for CDW3. - **-4** **--cdw10** *value* 32-bit value for CDW10. - **-5** **--cdw11** *value* 32-bit value for CDW11. - **-6** **--cdw12** *value* 32-bit value for CDW12. - **-7** **--cdw13** *value* 32-bit value for CDW13. - **-8** **--cdw14** *value* 32-bit value for CDW14. - **-9** **--cdw15** *value* 32-bit value for CDW15. - **-l** **--data-len** Length of the data for I/O (bytes). - **-m** **--metadata-len** Length of the metadata segment for command (bytes). This is ignored and not implemented in [nvme(4)](/nvme/4.md). - **-f** **--flags** Nvme command flags. - **-n** **--namespace-id** Namespace ID for command (ignored for admin, defaults to device's namespace for io). - **-p** **--prefill** Value to prefill payload with. - **-b** **--raw-binary** Output in binary format (otherwise a hex dump is produced). - **-d** **--dry-run** Do not actually execute the command, but perform sanity checks on it. - **-r** **--read** Command reads data from the device. - **-s** **--show-command** Show all the command values on stdout. - **-w** **--write** Command writes data to the device. Send arbitrary commands to the device. Can be used to extract vendor specific logs. Transfers to/from the device possible, but limited to MAXPHYS bytes. Commands either read data or write it, but not both. Commands needing metadata are not supported by the [nvme(4)](/nvme/4.md) drive. ### discover List the remote controllers advertised by a remote Discovery Controller: - **-t** *transport* Transport to use. The default is *tcp*. - **-q** *HostNQN* NVMe Qualified Name to use for this host. By default an NQN is auto-generated from the current host's UUID. - **-v** Display the IDENTIFY\_CONTROLLER data for the Discovery Controller. ### connect Establish an association with the I/O controller named *SubNQN* at *address*. The address must include a port. An admin queue pair and one or more I/O queue pairs are created and handed off to the kernel to create a new controller device. - **-c** *cntl-id* Remote controller ID to request: - dynamic Request a dynamic controller ID for controllers using the dynamic controller model. This is the default. - static Request a dynamic controller ID for controllers using the static controller model. - *number* Request a specific controller ID for controllers using the static controller model. - **-F** Request submission queue flow control. By default submission queue flow control is disabled unless the remote controller requires it. - **-g** Enable TCP PDU header digests. - **-G** Enable TCP PDU data digests. - **-i** *queues* Number of I/O queue pairs to create. The default is 1. - **-k** *seconds* Keep Alive timer duration in seconds. The default is 120. - **-l** *seconds* Controller Loss timer duration in seconds. The default is 600. This timer starts when an association is lost with a remote I/O controller and is cancelled when a new association is established. If the timer expires, the controller device is deleted. A setting of zero disables this timer. - **-r** *seconds* Reconnect timer duration in seconds. The default is 10. When an association is lost with a remote I/O controller, the controller device will request reconnection via periodic [devctl(4)](/devctl/4.md) notifications until either a new association is established or the controller device is deleted. This timer sets the interval between each [devctl(4)](/devctl/4.md) notification. Note that the first notification is triggered immediately after an association is lost. A setting of zero disables this timer. - **-t** *transport* Transport to use. The default is *tcp*. - **-q** *HostNQN* NVMe Qualified Name to use for this host. By default an NQN is auto-generated from the current host's UUID. - **-Q** *entries* Number of entries in each I/O queue. The default is the minimum of 128 or the maximum queue size reported by the MQES field of the remote host's CAP property. ### connect-all Query the Discovery Controller at *address* and establish an association for each advertised I/O controller. The **-t** flag determines the transport used for the initial association with the Discovery Controller and defaults to *tcp*. All other flags are used to control properties of each I/O association as described above for the **connect** command. ### disconnect Delete the controller device associated with a remote I/O controller including any active association and open queues. ### reconnect Reestablish an association for the remote I/O controller associated with *device-id*. If an *address* is not provided, the resolved address and settings from the previous association are used to establish a new association. If an *address* is provided, the supplied address and command line flags are used to establish a new association. In this case, the address must include a port and the flags have the same meaning for the new association as described above for the **connect** command. ### telemetry-log Extract the telemetry log associated with *device-id*, using the specified parameters: - **-O** *output-file* Output file for the data. This parameter is mandatory. - **-d** *data-area* The data area is either 1, 2 or 3. - **-v** Verbose output reporting progress. This log can be quite large and take minutes to retrieve. ## DEVICE NAMES Where ⟨*namespace-id*⟩ is required, you can use either the *nvmeXnsY* device, or the disk device such as *ndaZ* or *nvdZ*. The leading */dev/* may be omitted. Where ⟨*device-id*⟩ is required, you can use either the *nvmeX* device, or the disk device such as *ndaZ* or *nvdZ*. For commands that take an optional ⟨nsid⟩ you can use it to get information on other namespaces, or to query the drive itself. A ⟨nsid⟩ of “0” means query the drive itself. ## FABRICS TRANSPORTS The following NVM Express over Fabrics transports are supported for accessing remote controllers: - tcp TCP transport ## NETWORK ADDRESSES Network addresses for remote controllers can use one of the following formats: - \[*IPv6* *address*\]:*port* - *IPv4* *address*:*port* - *hostname*:*port* - \[*IPv6* *address*\] - *IPv6* *address* - *IPv4* *address* - *hostname* If a *port* is not provided, a default value is used if possible. ## EXAMPLES ``` nvmecontrol devlist ``` Display a list of NVMe controllers and namespaces along with their device nodes. ``` nvmecontrol identify nvme0 ``` ``` nvmecontrol identify -n 0 nvd0 ``` Display a human-readable summary of the nvme0 IDENTIFY\_CONTROLLER data. In this example, nvd0 is connected to nvme0. ``` nvmecontrol identify -x -v nvme0ns1 ``` ``` nvmecontrol identify -x -v -n 1 nvme0 ``` Display an hexadecimal dump of the nvme0 IDENTIFY\_NAMESPACE data for namespace 1. ``` nvmecontrol perftest -n 32 -o read -s 512 -t 30 nvme0ns1 ``` Run a performance test on nvme0ns1 using 32 kernel threads for 30 seconds. Each thread will issue a single 512 byte read command. Results are printed to stdout when 30 seconds expires. ``` nvmecontrol reset nvme0 ``` ``` nvmecontrol reset nda4 ``` Perform a controller-level reset of the nvme0 controller. In this example, nda4 is wired to nvme0. ``` nvmecontrol logpage -p 1 nvme0 ``` Display a human-readable summary of the nvme0 controller's Error Information Log. Log pages defined by the NVMe specification include Error Information Log (ID=1), SMART/Health Information Log (ID=2), and Firmware Slot Log (ID=3). ``` nvmecontrol logpage -p 0xc1 -v wdc nvme0 ``` Display a human-readable summary of the nvme0's wdc-specific advanced SMART data. ``` nvmecontrol logpage -p 1 -x nvme0 ``` Display a hexadecimal dump of the nvme0 controller's Error Information Log. ``` nvmecontrol logpage -p 0xcb -b nvme0 > /tmp/page-cb.bin ``` Print the contents of vendor specific page 0xcb as binary data on standard out. Redirect it to a temporary file. ``` nvmecontrol firmware -s 2 -f /tmp/nvme_firmware nvme0 ``` Download the firmware image contained in "/tmp/nvme\_firmware" to slot 2 of the nvme0 controller, but do not activate the image. ``` nvmecontrol firmware -s 4 -a nvme0 ``` Activate the firmware in slot 4 of the nvme0 controller on the next reset. ``` nvmecontrol firmware -s 7 -f /tmp/nvme_firmware -a nvme0 ``` Download the firmware image contained in "/tmp/nvme\_firmware" to slot 7 of the nvme0 controller and activate it on the next reset. ``` nvmecontrol power -l nvme0 ``` List all the current power modes. ``` nvmecontrol power -p 3 nvme0 ``` Set the current power mode. ``` nvmecontrol power nvme0 ``` Get the current power mode. ``` nvmecontrol identify -n 0 nda0 ``` Identify the drive data associated with the *nda0* device. The corresponding *nvmeX* devices is used automatically. ``` nvmecontrol identify nda0 ``` Get the namespace parameters associated with the *nda0* device. The corresponding *nvmeXnsY* device is used automatically. ``` nvmecontrol format -f 2 -m 0 -p 0 -l 0 -C nvme2 ``` Format all the name spaces on nvme2 using parameters from “LBA Format #2” with no metadata or protection data using cryptographic erase. If the “nvmecontrol identify -n 1 nvme2” command ended with ``` LBA Format #00: Data Size: 512 Metadata Size: 0 Performance: Good LBA Format #01: Data Size: 512 Metadata Size: 8 Performance: Good LBA Format #02: Data Size: 4096 Metadata Size: 0 Performance: Good LBA Format #03: Data Size: 4096 Metadata Size: 8 Performance: Good LBA Format #04: Data Size: 4096 Metadata Size: 64 Performance: Good ``` then this would give a 4k data format for at least namespace 1, with no metadata. ## DYNAMIC LOADING The directories */lib/nvmecontrol* and */usr/local/lib/nvmecontrol* are scanned for any .so files. These files are loaded. The members of the *top* linker set are added to the top-level commands. The members of the *logpage* linker set are added to the logpage parsers. ## SEE ALSO *The NVM Express Base Specification*, June 10, 2019, https://nvmexpress.org/wp-content/uploads/NVM-Express-1\_4-2019.06.10-Ratified.pdf. ## HISTORY The **nvmecontrol** utility appeared in FreeBSD 9.2. ## AUTHORS **nvmecontrol** was developed by Intel and originally written by Jim Harris ⟨*jimharris@FreeBSD.org*⟩. This man page was written by Jim Harris ⟨*jimharris@FreeBSD.org*⟩.