Managing Removable Media (Overview)

The following information is described in this section:

• Removable Media Features and Benefits

• Comparison of Manual and Automatic Mounting

• Overview of Accessing Removable Media

Removable Media Features and Benefits

The Oracle Solaris release gives users and software developers a standard interface for dealing with removable media. Removable media services provide the following benefits:

• Automatically mounts removable media. For a comparison of manual and automatic mounting, see the following section.

• Enables you to access removable media without having to become an administrator.

• Allows you to give other systems on the network automatic access to any removable media on your local system. For more information, see Accessing Removable Media on a Remote System.

vold is Managed by the Service Management Facility (SMF)

The volume management daemon, vold, is managed by the Service Management Facility (SMF). This means you can use the svcadm disable command to disable the following new volfs service, if appropriate:

# svcadm disable volfs

You can identify the status of the volfs service by using this command:

$ svcs volfs
STATE          STIME    FMRI
online         Sep_29   svc:/system/filesystem/volfs:default

For more information, see smf(5).

You can use the svccfg command to display and to set additional vold properties. For example, you could temporarily enable vold logging to help troubleshooting a problem. For example:

# svccfg
svc:> select system/filesystem/volfs
svc:/system/filesystem/volfs> setprop vold/log_debuglevel=3
svc:/system/filesystem/volfs> exit
# svcadm disable volfs
# svcadm enable volfs

You can also use the svccfg command to display a listing of settable vold properties.

# svccfg
svc:> select volfs
svc:/system/filesystem/volfs> listprop vold/*
vold/config_file            astring  
vold/log_debuglevel         count    3
vold/log_file               astring  
vold/log_nfs_trace          boolean  false
vold/log_verbose            boolean  false
vold/root_dir               astring  
vold/never_writeback_label  boolean  false
svc:/system/filesystem/volfs> exit

For a description of these properties, see the vold(1M).

Volume Management (vold) Improvements

Device links are properly created for devices that contain no media, similar to the following:

lrwxrwxrwx   1 root     root     28 Jun 13 13:09 /vol/dev/aliases/cdrom0 ->
 /vol/dev/rdsk/c2t2d0/nomedia

You can use the cdrw and rmformat commands to list devices that have no media when vold is running.

You can revert back to the previous vold behavior by changing the following support nomedia entry in the /etc/vold.conf file as follows:

support media

Then, restart vold. For more information, see vold.conf(4).

In addition, vold is now hot-plug aware. This improvement means that if you insert removable media, the media is automatically detected and mounted by vold. There should be no need to restart vold manually to recognize and mount a file system from any removable media device.

If you are using a legacy or non-USB diskette device, then you might need to issue the volcheck command before vold can recognize the media.

If the media is detected, but for some reason, is unmounted, then you'll need to run the following commands:

# volrmmount -i rmdisk0

Before you hot-remove a removable media device, eject the media first. For example:

# eject rmdisk0

Comparison of Manual and Automatic Mounting

The following table compares the steps involved in manual mounting (without removable media services) and automatic mounting (with removable media management) of removable media.

Table 1-1 Comparison of Manual and Automatic Mounting of Removable Media

Overview of Accessing Removable Media

Essentially, removable media services enable you to access removable media just as manual mounting does, but more easily and without the need for administrative access.

If your system has more than one type of removable device, see the following table for their access points.

Table 1-2 Where to Access Removable Media

You can use the rmmount -l command to identify mounted media on your system. For example:

# rmmount -l
/dev/dsk/c5t0d0p0       rmdisk6,/media/FD-05PUB
/dev/dsk/c4t0d3p0       rmdisk5,/media/223UHS-SD-MMC
/dev/dsk/c2t0d0s2       cdrom1,cd1,sr1,Oracle_Solaris-11_1-AI-SPARC,/media/Oracle_Solaris-11_1-AI-SPARC
/dev/dsk/c3t0d0p0       rmdisk2,/media/00JB-00CRA0

In the above output, the mounted devices are as follows:

/dev/dsk/c5t0d0p0

USB diskette

/dev/dsk/c4t0d3p0

CF card in a USB card reader

/dev/dsk/c2t0d0s2

DVD-ROM

/dev/dsk/c3t0d0p0

Removable USB disk