NVME-FABRICS.CONF(5) NVMe Manual NVME-FABRICS.CONF(5)

# [NAME](#NAME)

nvme-fabrics.conf - NVMe-oF connection configuration file format

# [SYNOPSIS](#SYNOPSIS)

```
/usr/local/etc/nvme/nvme-fabrics.conf
/usr/local/etc/nvme/nvme-fabrics.conf.d/*.conf
```

# [DESCRIPTION](#DESCRIPTION)

An INI-format file describing which NVMe over Fabrics (NVMe-oF) controllers a host should connect to, and with what parameters. This file is read by *nvme connect-all*, *nvme discover* and *nvme connect*, and by the nvme-discoverd daemon.

Other orchestrators read the same format through the same parser, but from a file of their own: nvme-stas reads its configuration through the Python bindings. The file name is a parameter of every entry point, so each orchestrator names its own and is unaffected by the others'.

A configuration is a main file plus an optional drop-in directory, the same *foo.conf* + *foo.conf.d/* pattern systemd uses. Both parts are read independently, and either may be absent; an absent configuration is not an error; it simply yields no connections.

--config FILE (on *connect-all*/*discover*/*connect*) names the main file; its drop-in directory is always *FILE.d/*. Omitting --config uses the default path above.

# [SECTIONS](#SECTIONS)

Each section is one or more *key = value* lines. An empty value (*key =*) resets the key to the kernel default, overriding whatever an outer scope set (see RESETTING A KEY below). Unknown keys are ignored. Boolean values accept *1*/*yes*/*y*/*true*/*t*/*on* and *0*/*no*/*n*/*false*/*f*/*off* (case-insensitive).

*\[Host]*

Optional, at most one per file. The identity used by every connection in that file: *hostnqn*, *hostid*, *hostsymname*, plus any SECURITY key below. A file with no *\[Host]* connects as the system default identity (*/usr/local/etc/nvme/hostnqn* / *hostid*). A drop-in that defines *\[Host]* must set *hostnqn* explicitly.

*\[Discovery Controller Defaults]*, *\[I/O Controller Defaults]*

Optional, at most one of each per file. Default TUNABLE values for connections of that class, drawn from below. A drop-in’s copy overlays the top-level file’s, for that drop-in’s own connections only.

*\[Discovery Controller]*

One Discovery Controller to connect to. Repeatable. *nqn =* defaults to the well-known discovery NQN if omitted.

*\[Subsystem]*

One I/O subsystem to connect to, named by *nqn =*. Repeatable.

Both endpoint sections accept any TUNABLE or SECURITY key as a per-section override, plus one or more *controller =* lines (below).

# [CONTROLLER LINES](#CONTROLLER_LINES)

Each *controller =* line under a *\[Discovery Controller]* or *\[Subsystem]* section is one path to that endpoint; repeating the key expresses multipath (native NVMe multipath groups all paths sharing a subsysnqn). The value is a *;*-separated *key=value* list:

```
controller = transport=tcp;traddr=10.0.0.9;trsvcid=4420;host-iface=eth0
```

*transport* and *traddr* are required; *trsvcid*, *host-traddr* and *host-iface* are optional. Any TUNABLE key may also appear on the line as a per-path override — SECURITY keys may not, since they are bound to the (host, subsystem) pair, not to a single path.

# [KEYS](#KEYS)

TUNABLE (type default, *\[Host]*, endpoint section, or *controller =* line):

```
nr-io-queues, nr-write-queues, nr-poll-queues, queue-size,
keep-alive-tmo, reconnect-delay, ctrl-loss-tmo, fast-io-fail-tmo,
tos, duplicate-connect, disable-sqflow, hdr-digest, data-digest
```

SECURITY (*\[Host]* or endpoint section only, never a *controller =* line):

```
tls, tls-key, tls-key-identity, keyring, concat, kxchap-secret,
kxchap-ctrl-secret
```

IDENTITY (*\[Host]* only):

```
hostnqn, hostid, hostsymname
```

Every key here is the same name as its *nvme connect* long option (hyphenated). See [**nvme-connect**(1)](/man/os/nvme-cli/nvme-connect.1) for what each one means.

# [RESETTING A KEY](#RESETTING_A_KEY)

An empty assignment (*key =*) resets that key to the kernel default, undoing whatever an outer scope (a *\*Defaults* section or *\[Host]*) set. This differs from simply not writing the key, which instead inherits through the cascade below.

# [PRECEDENCE](#PRECEDENCE)

A key resolves most-specific first:

```
controller = line > endpoint section > [Host] > type defaults > kernel default
```

The type-defaults level is chosen by the connection’s class: a Discovery Controller draws from *\[Discovery Controller Defaults]*, an I/O Controller from *\[I/O Controller Defaults]*.

# [EXAMPLE](#EXAMPLE)

```
# /usr/local/etc/nvme/nvme-fabrics.conf
[Discovery Controller Defaults]
keep-alive-tmo = 30
[I/O Controller Defaults]
keep-alive-tmo = 5
[Host]
hostsymname = lab-host-01
[Discovery Controller]
controller = transport=tcp;traddr=192.168.1.10;trsvcid=8009
[Subsystem]
nqn        = nqn.2024-01.com.example:data.vol1
controller = transport=tcp;traddr=192.168.1.20;trsvcid=4420
controller = transport=tcp;traddr=192.168.1.21;trsvcid=4420
```

See */usr/local/etc/nvme/nvme-fabrics.conf.sample* for a longer, commented example.

# [SEE ALSO](#SEE_ALSO)

[nvme-connect-all(1)](/man/os/nvme-cli/nvme-connect-all.1) [nvme-discover(1)](/man/os/nvme-cli/nvme-discover.1) [nvme-connect(1)](/man/os/nvme-cli/nvme-connect.1) [nvme-config-convert(1)](/man/os/nvme-cli/nvme-config-convert.1) **https://github.com/linux-nvme/nvme-cli/blob/master/libnvme/design/CONFIG.md**

# [NVME](#NVME)

Part of the nvme-user suite

09/18/2026 NVMe

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Document: nvme-fabrics.conf(5) from nvme-cli 3.1-r1 (Chainguard OS)
Source: https://github.com/linux-nvme/nvme-cli