1NVME-CONNECT(1) NVMe Manual NVME-CONNECT(1)
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6 nvme-connect - Connect to a Fabrics controller.
7
9 nvme connect
10 [--transport=<trtype> | -t <trtype>]
11 [--nqn=<subnqn> | -n <subnqn>]
12 [--traddr=<traddr> | -a <traddr>]
13 [--trsvcid=<trsvcid> | -s <trsvcid>]
14 [--host-traddr=<traddr> | -w <traddr>]
15 [--host-iface=<iface> | -f <iface>]
16 [--hostnqn=<hostnqn> | -q <hostnqn>]
17 [--hostid=<hostid> | -I <hostid>]
18 [--config-file=<cfg> | -J <cfg> ]
19 [--dhchap-secret=<secret> | -S <secret>]
20 [--dhchap-ctrl-secret=<secret> | -C <secret>]
21 [--nr-io-queues=<#> | -i <#>]
22 [--nr-write-queues=<#> | -W <#>]
23 [--nr-poll-queues=<#> | -P <#>]
24 [--queue-size=<#> | -Q <#>]
25 [--keep-alive-tmo=<#> | -k <#>]
26 [--reconnect-delay=<#> | -c <#>]
27 [--ctrl-loss-tmo=<#> | -l <#>]
28 [--duplicate-connect | -D]
29 [--disable-sqflow | -d]
30 [--hdr-digest | -g]
31 [--data-digest | -G]
32 [--dump-config | -O]
33 [--output-format=<fmt> | -o <fmt>]
34
36 Create a transport connection to a remote system (specified by --traddr
37 and --trsvcid) and create a NVMe over Fabrics controller for the NVMe
38 subsystem specified by the --nqn option.
39
41 -t <trtype>, --transport=<trtype>
42 This field specifies the network fabric being used for a
43 NVMe-over-Fabrics network. Current string values include:
44 ┌──────┬────────────────────────────┐
46 │Value │ Definition │
47 ├──────┼────────────────────────────┤
48 │rdma │ The network fabric is an │
49 │ │ rdma network (RoCE, iWARP, │
50 │ │ Infiniband, basic rdma, │
51 │ │ etc) │
52 ├──────┼────────────────────────────┤
53 │fc │ WIP The network fabric is │
54 │ │ a Fibre Channel network. │
55 ├──────┼────────────────────────────┤
56 │tcp │ The network fabric is a │
57 │ │ TCP/IP network. │
58 ├──────┼────────────────────────────┤
59 │loop │ Connect to a NVMe over │
60 │ │ Fabrics target on the │
61 │ │ local host │
62 └──────┴────────────────────────────┘
63 -n <subnqn>, --nqn <subnqn>
65 This field specifies the name for the NVMe subsystem to connect to.
66 -a <traddr>, --traddr=<traddr>
68 This field specifies the network address of the Controller. For
69 transports using IP addressing (e.g. rdma) this should be an
70 IP-based address (ex. IPv4).
71 -s <trsvcid>, --trsvcid=<trsvcid>
73 This field specifies the transport service id. For transports using
74 IP addressing (e.g. rdma) this field is the port number. By
75 default, the IP port number for the RDMA transport is 4420.
76 -w <traddr>, --host-traddr=<traddr>
78 This field specifies the network address used on the host to
79 connect to the Controller. For TCP, this sets the source address on
80 the socket.
81 -f <iface>, --host-iface=<iface>
83 This field specifies the network interface used on the host to
84 connect to the Controller (e.g. IP eth1, enp2s0, enx78e7d1ea46da).
85 This forces the connection to be made on a specific interface
86 instead of letting the system decide.
87 -q <hostnqn>, --hostnqn=<hostnqn>
89 Overrides the default Host NQN that identifies the NVMe Host. If
90 this option is not specified, the default is read from
91 /etc/nvme/hostnqn first. If that does not exist, the autogenerated
92 NQN value from the NVMe Host kernel module is used next. The Host
93 NQN uniquely identifies the NVMe Host.
94 -I <hostid>, --hostid=<hostid>
96 UUID(Universally Unique Identifier) to be discovered which should
97 be formatted.
98 -J <cfg>, --config-file=<cfg>
100 Use the specified JSON configuration file instead of the default
101 /etc/nvme/config.json file or none to not read in an existing
102 configuration file. The JSON configuration file format is
103 documented in
104 https://github.com/linux-nvme/libnvme/doc/config-schema.json
105 -S <secret>, --dhchap-secret=<secret>
107 NVMe In-band authentication secret; needs to be in ASCII format as
108 specified in NVMe 2.0 section 8.13.5.8 Secret representation. If
109 this option is not specified, the default is read from
110 /etc/nvme/hostkey. If that does not exist no in-band authentication
111 is attempted.
112 -C <secret>, --dhchap-ctrl-secret=<secret>
114 NVMe In-band authentication controller secret for bi-directional
115 authentication; needs to be in ASCII format as specified in NVMe
116 2.0 section 8.13.5.8 Secret representation. If not present
117 bi-directional authentication is not attempted.
118 -i <#>, --nr-io-queues=<#>
120 Overrides the default number of I/O queues create by the driver.
121 -W <#>, --nr-write-queues=<#>
123 Adds additional queues that will be used for write I/O.
124 -P <#>, --nr-poll-queues=<#>
126 Adds additional queues that will be used for polling latency
127 sensitive I/O.
128 -Q <#>, --queue-size=<#>
130 Overrides the default number of elements in the I/O queues created
131 by the driver.
132 -k <#>, --keep-alive-tmo=<#>
134 Overrides the default keep alive timeout (in seconds).
135 -c <#>, --reconnect-delay=<#>
137 Overrides the default delay (in seconds) before reconnect is
138 attempted after a connect loss.
139 -l <#>, --ctrl-loss-tmo=<#>
141 Overrides the default controller loss timeout period (in seconds).
142 -D, --duplicate-connect
144 Allows duplicated connections between same transport host and
145 subsystem port.
146 -d, --disable-sqflow
148 Disables SQ flow control to omit head doorbell update for
149 submission queues when sending nvme completions.
150 -g, --hdr-digest
152 Generates/verifies header digest (TCP).
153 -G, --data-digest
155 Generates/verifies data digest (TCP).
156 -O, --dump-config
158 Print out resulting JSON configuration file to stdout.
159 -o <format>, --output-format=<format>
161 Set the reporting format to normal or json. Only one output format
162 can be used at a time. When this option is specified, the device
163 associated with the connection will be printed. Nothing is printed
164 otherwise.
165
167 • Connect to a subsystem named
168 nqn.2014-08.com.example:nvme:nvm-subsystem-sn-d78432 on the IP4
169 address 192.168.1.3. Port 4420 is used by default:
170 # nvme connect --transport=rdma --traddr=192.168.1.3 \
172 --nqn=nqn.2014-08.com.example:nvme:nvm-subsystem-sn-d78432
173
175 nvme-discover(1) nvme-connect-all(1)
176
178 This was co-written by Jay Freyensee[1] and Christoph Hellwig[2]
179
181 Part of the nvme-user suite
182
184 1. Jay Freyensee
185 mailto:james.p.freyensee@intel.com
186 2. Christoph Hellwig
188 mailto:hch@lst.de
189NVMe 11/04/2022 NVME-CONNECT(1)