HP-UX Reference (11i v2 04/09) - 1M System Administration Commands A-M (vol 3)

ManualsBrandsHP ManualsSoftwareHP-UX Reference Manuals

491

492

493

494

495

496

497

498

499

500

mount_vxfs(1M) mount_vxfs(1M)

The ﬁrst node to mount special is called the primary node. The primary node handles

intent logging for the cluster. Other nodes are called secondary nodes. A secondary writ-

able node (rw) is not allowed if the primary node is mounted as read-only (

ro).

convosync=direct|dsync|unbuffered|closesync|delay

Alters the caching behavior of the ﬁle system for

O_SYNC and O_DSYNC I/O operations.

The

direct value handles any reads or writes with the

O_SYNC or O_DSYNC ﬂag as if the

VX_DIRECT caching advisory is set.

The

dsync value handles any writes with the

O_SYNC ﬂag as if the VX_DSYNC caching

advisory is set. It does not modify behavior for writes with

O_DSYNC set.

The

unbuffered value handles any reads or writes with the

O_SYNC or O_DSYNC ﬂag as

if the

VX_UNBUFFERED

caching advisory is set.

The

closesync value delays O_SYNC or O_DSYNC writes so that they do not take effect

immediately.

The

closesync, dsync, direct, and

unbuffered values all run the equivalent of an

fsync(2) to be run when any ﬁle accessed with the

O_SYNC or O_DSYNC ﬂag is closed.

The

delay value delays O_SYNC or O_DSYNC writes so that they do not take effect

immediately. With this option, VxFS changes O_SYNC or O_DSYNC writes into delayed

writes. No special action is performed when closing a ﬁle. This option effectively cancels

data integrity guarantees normally provided by opening a ﬁle with O_SYNC or O_DSYNC.

Note: The

convosync option is available only with the HP OnLineJFS product.

crw The cluster read-write option allows asymmetric mounts, that is, you can mount a speciﬁed

cluster ﬁle system in read-only or read-write mode independently of the other shared ﬁle

system nodes. crw must be speciﬁed with the -o cluster option. Without specifying

crw, the default functionality of the cluster mount is retained; the read-write capability of

cluster secondaries are the same as the cluster primary. You can use the crw in conjunc-

tion with rw or ro as shown in the following mount compatibility matrix:

Secondary

------- ----------------------------------

Primary ro rw ro,crw rw,crw

------- ----------------------------------

ro yes no no no

rw no yes yes yes

ro,crw no yes yes yes

rw,crw no yes yes yes

If the primary is mounted with ro,crw,orrw,crw as shown in the ﬁrst column, the secon-

dary read and write capabilities can still be set independently. For a cluster mount,

rw on

the primary enables cluster-wide read-write capability.

The read and write capabilities can be changed from its original setting to another using

the

-o remount option. The read and write capabilities can be changed according to the

following matrix:

------- ----------------------------------

From/To ro rw ro,crw rw,crw

------- ----------------------------------

ro no yes yes yes

rw no yes no yes

ro,crw no yes yes yes

rw,crw no yes no yes

If a cluster ﬁle system is mounted read-write (rw), the underlying disk group must have the

activation mode attribute set to sharedwrite (sw).

If a cluster ﬁle system is mounted

ro,crw, and the disk group activation mode is

sharedread (sr), that cluster ﬁle system can never be a primary, and must be mounted

seconly (see the seconly option in this section). See the VERITAS SANPoint Founda-

tion Suite Installation and Conﬁguration Guide.

Section 1M−−476 Hewlett-Packard Company − 3 − HP-UX 11i Version 2: September 2004