|
|
HP-UX Reference > Vvgextend(1M)HP-UX 11i Version 2: December 2007 Update |
|
NAMEvgextend — extend an LVM volume group by adding physical volumes DESCRIPTIONThe vgextend command assigns additional physical volumes to volume group vg_name. The volume group must be active. Volume groups are extended by adding one or more physical volumes specified by pv_path ... After the physical volumes have been successfully added to the volume group, the disk space they contain can be allocated to logical volumes. Before assigning an additional physical volume to a volume group, create the physical volume with the pvcreate command (see pvcreate(1M)). Then, create the volume group with the vgcreate command, assigning at least one physical volume (see vgcreate(1M)). If, for any reason, a specified physical volume cannot be installed into the volume group, an error message is displayed. However, the installation continues to the end of the list of physical volumes. When a pv_path refers to one of the physical volumes already in the volume group by a different pv_path name to indicate the use of a different controller, this new path becomes an alternate link to the physical volume. When two paths that reference the same disk are provided in the pv_path list, the order of the paths is important. The first path becomes the "primary link" to the physical volume, the second becomes an "alternate link" to the physical volume. The primary link is the path used to access the physical volume unless the primary link becomes unavailable in which case LVM automatically switches to the alternate link to access the physical volume. Currently LVM supports a maximum of 8 paths to a physical volume (7 alternates and one primary). Options and Argumentsvgextend recognizes the following options and arguments:
EXTERNAL INFLUENCESEnvironment VariablesLANG determines the language in which messages are displayed. If LANG is not specified or is null, it defaults to "C" (see lang(5)). If any internationalization variable contains an invalid setting, all internationalization variables default to "C" (see environ(5)). EXAMPLESAdd physical volumes /dev/dsk/c0t1d0 and /dev/dsk/c0t2d0 to volume group /dev/vg03: vgextend /dev/vg03 /dev/dsk/c0t1d0 /dev/dsk/c0t2d0 Extend physical volume group PVG0 while adding physical volumes /dev/dsk/c0t3d0 and /dev/dsk/c0t4d0 to volume group /dev/vg03: vgextend -g PVG0 /dev/vg03 /dev/dsk/c0t3d0 /dev/dsk/c0t4d0 Add an alternate link to one of the physical volumes in the volume group where /dev/dsk/c0t4d0 and /dev/dsk/c1t4d0 refer to the same physical volume (referenced via different controllers), and the volume group already contains /dev/dsk/c0t4d0. /dev/dsk/c0t4d0 remains the primary link (in use) and /dev/dsk/c1t4d0 becomes the alternate link. vgextend /dev/vg03 /dev/dsk/c1t4d0 Add a spare physical volume to a volume group: vgextend -z y /dev/vg03 /dev/dsk/c2t4d0 WARNINGSThe new physical volume which has been added to the volume group could potentially have a different block size compared to physical volumes already in the volume group. If a logical volume is created on two or more physical volumes which have a different block size, it is not possible to use such logical volume for file system purposes. See extendfs(1M). For example, when a logical volume contains physical volumes that all have 1k block size, and then it is extended to contain a physical volume with 2k block size, then the block size of the volume group is increased to 2k. ADDITIONAL WARNINGSStarting at 10.20, the vgextend command is supporting additional EMC Symmetrix disk product functionality (see vgchgid(1M)). The vgextend command will be enforcing a new rule such that a physical device, to be extended to a volume group, must have the same EMC Symmetrix attributes as the physical volumes already in the volume group. Clearly this checking only applies if the disks involved (those already in the volume group and those being added) in the operation are EMC Symmetrix. Should the command find an incompatibility, a message of the following type will be produced:
|
|