nbdkit-client(1)

NAME
nbdkit-client - how to mount NBD filesystems on a client machine

DESCRIPTION
For NBD exports that contain filesystems there are several approaches to mounting them on a client machine.

To ensure the nbd kernel module is loaded you may need to do:

 # echo nbd > /etc/modules-load.d/nbd.conf

This will not take effect until you reboot, so also do:

 # modprobe nbd

  Easy mounting at boot time
For simple setups the following method is the easiest way to get an NBD filesystem to mount at boot. Create or edit /etc/rc.local or /etc/rc.d/rc.local:

 #!/bin/sh -
 nm-online
 modprobe nbd
 nbd-client server /dev/nbd0
 mount /dev/nbd0 /mnt

  Mounting using systemd mount points
You can use systemd mount points to mount NBD filesystems at boot and/or on demand.

Set up an nbdtab(5) mapping. If /etc/nbdtab doesn't exist, then create it first. Add this line:

 nbd0 server / bs=512,persist

As a workaround for https://github.com/NetworkBlockDevice/nbd/issues/91 you must currently modify the nbd@.service file:

 # cp /usr/lib/systemd/system/nbd@.service /etc/systemd/system/
 # vi /etc/systemd/system/nbd@.service

and edit or create these settings in the "[Service]" section:

 [Service]
 Type=oneshot
 RemainAfterExit=yes
 ExecStart=/usr/sbin/nbd-client %i
 ExecStop=/usr/sbin/nbd-client -d /dev/%i

Finally create a systemd mount file called /etc/systemd/system/mnt.mount:

 [Unit]
 Requires=nbd@nbd0.service
 [Mount]
 What=/dev/nbd0
 Where=/mnt
 Type=ext4

You can either reboot now or do:

 # systemctl start mnt.mount

Other systemd services which need this mount point can depend on this mount unit.

SEE ALSO
nbdkit(1), nbdkit-loop(1), nbdkit-service(1), nbd-client(8), nbdtab(5), systemd(1), systemd.mount(5).

AUTHORS
Richard W.M. Jones

COPYRIGHT
Copyright (C) 2013-2020 Red Hat Inc.

LICENSE
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