RAMDISKADM(8) Maintenance Commands and Procedures RAMDISKADM(8)

NAME

ramdiskadm - administer ramdisk pseudo device

SYNOPSIS

/usr/sbin/ramdiskadm -a name size [g | m | k | b]


/usr/sbin/ramdiskadm -d name


/usr/sbin/ramdiskadm

DESCRIPTION

The ramdiskadm command administers ramdisk(4D), the ramdisk driver.
Use ramdiskadm to create a new named ramdisk device, delete an
existing named ramdisk, or list information about existing ramdisks.


Ramdisks created using ramdiskadm are not persistent across reboots.

OPTIONS

The following options are supported:

-a name size
Create a ramdisk named name of size size and its
corresponding block and character device nodes.

name must be composed only of the characters a-z, A-
Z, 0-9, _ (underbar), and - (hyphen), but it must not
begin with a hyphen. It must be no more than 32
characters long. Ramdisk names must be unique.

The size can be a decimal number, or, when prefixed
with 0x, a hexadecimal number, and can specify the
size in bytes (no suffix), 512-byte blocks (suffix
b), kilobytes (suffix k), megabytes (suffix m) or
gigabytes (suffix g). The size of the ramdisk
actually created might be larger than that specified,
depending on the hardware implementation.

If the named ramdisk is successfully created, its
block device path is printed on standard out.


-d name
Delete an existing ramdisk of the name name. This
command succeeds only when the named ramdisk is not
open. The associated memory is freed and the device
nodes are removed.

You can delete only ramdisks created using
ramdiskadm. It is not possible to delete a ramdisk
that was created during the boot process.


Without options, ramdiskadm lists any existing ramdisks, their sizes
(in decimal), and whether they can be removed by ramdiskadm (see the
description of the -d option, above).

EXAMPLES

Example 1: Creating a 2MB Ramdisk Named mydisk

# ramdiskadm -a mydisk 2m
/dev/ramdisk/mydisk

Example 2: Listing All Ramdisks

# ramdiskadm
Block Device Size Removable
/dev/ramdisk/miniroot 134217728 No
/dev/ramdisk/certfs 1048576 No
/dev/ramdisk/mydisk 2097152 Yes

EXIT STATUS

ramdiskadm returns the following exit values:

0
Successful completion.


>0
An error occurred.

ATTRIBUTES

See attributes(7) for descriptions of the following attributes:


+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Evolving |
+--------------------+-----------------+

SEE ALSO

ramdisk(4D), attributes(7)

NOTES

The abilities of ramdiskadm and the privilege level of the person who
uses the utility are controlled by the permissions of
/dev/ramdiskctl. Read access allows query operations, for example,
listing device information. Write access is required to do any
state-changing operations, for example, creating or deleting
ramdisks.


As shipped, /dev/ramdiskctl is owned by root, in group sys, and mode
0644, so all users can do query operations but only root can perform
state-changing operations. An administrator can give write access to
non-privileged users, allowing them to add or delete ramdisks.
However, granting such ability entails considerable risk; such
privileges should be given only to a trusted group.

March 25, 2003 RAMDISKADM(8)