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xbdback(4) [netbsd man page]

XBDBACK(4)						 BSD/xen Kernel Interfaces Manual						XBDBACK(4)

NAME
xbdback -- Xen backend paravirtualized block device interface SYNOPSIS
pseudo-device xbdback DESCRIPTION
The xbdback interface forms the backend part of the paravirtualized drivers used by Xen domains to offer a block device interface, similar to a hard disk. xbdback interfaces are backed either by a physical device directly, or an image file mounted through vnd(4). All xbdback interfaces follow the ``xbdbackXiY'' naming convention, where 'X' represents the guest domain identifier, and 'Y' an arbitrary identifier. This identifier is usually associated to the device node as seen by the guest using major(3) and minor(3) numbers. For example, identifier ``769'' (0x301) means major 3 and minor 1, identified as ``hda1'' under Linux convention. For NetBSD, the guest device name spec- ified in the guest configuration file does not matter, and can be chosen arbitrarily. A xbdback interface will appear as a xbd(4) block device inside a NetBSD guest domain. In the XenStore, xbd and xbdback are identified by ``vbd'' (virtual block device) entries. DIAGNOSTICS
xbd backend: attach device %s (size %d) for domain %d Gives the device used as xbdback interface for the given guest domain, and its size, in bytes. xbd backend 0x%x for domain %d using event channel %d, protocol %s Gives the backend identifier, guest domain ID, event channel ID, and pro- tocol used for block level communication. xbdback %s: can't VOP_OPEN device 0x%x: %d When this message appears in the system message buffer with error 16 (EBUSY), the device is likely to be already mounted. It must be unmounted first, as the system will refuse to open it a second time. SEE ALSO
vnd(4), xbd(4), xenbus(4) HISTORY
The xbdback driver first appeared in NetBSD 4.0. AUTHORS
The xbdback driver was written by Manuel Bouyer <bouyer@NetBSD.org>. BSD
June 7, 2011 BSD

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MKNOD(8)						    BSD System Manager's Manual 						  MKNOD(8)

NAME
mknod -- make device special file SYNOPSIS
mknod [-F format] name [c | b] major minor mknod [-F format] name [c | b] major unit subunit mknod name [c | b] number mknod name w DESCRIPTION
The mknod command creates device special files. To make nodes manually, the required arguments are: name Device name, for example ``sd'' for a SCSI disk on an HP300 or a ``pty'' for pseudo-devices. b | c | w Type of device. If the device is a block type device such as a tape or disk drive which needs both cooked and raw special files, the type is b. Whiteout nodes are type w. All other devices are character type devices, such as terminal and pseudo devices, and are type c. major The major device number is an integer number which tells the kernel which device driver entry point to use. minor The minor device number tells the kernel which one of several similar devices the node corresponds to; for example, it may be a spe- cific serial port or pty. unit and subunit The unit and subunit numbers select a subset of a device; for example, the unit may specify a particular SCSI disk, and the subunit a partition on that disk. (Currently this form of specification is only supported by the bsdos format, for compatibility with the BSD/OS mknod(8).) Device numbers for different operating systems may be packed in a different format. To create device nodes that may be used by such an oper- ating system (e.g. in an exported file system used for netbooting), the -F option is used. The following formats are recognized: native, 386bsd, 4bsd, bsdos, freebsd, hpux, isc, linux, netbsd, osf1, sco, solaris, sunos, svr3, svr4 and ultrix. Alternatively, a single opaque device number may be specified. SEE ALSO
mkfifo(1), mkfifo(2), mknod(2) HISTORY
A mknod command appeared in Version 6 AT&T UNIX. The -F option appeared in NetBSD 1.4. NetBSD 1.4 September 11, 1998 NetBSD 1.4
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