updatevsdnode Command

Purpose

Modifies virtual shared disk subsystem options.

Syntax

updatevsdnode: -n {ALL | node_number [,node_number …]}
: {[-a VSD_adapter]
: [-b min_buddy_buffer_size]
: [-x max_buddy_buffer_size
: [-s max_buddy_buffers]
: [-M vsd_max_ip_packet_size]}
: [-f] [-c cluster_name | NONE]

Description

Use updatevsdnode to modify virtual shared disk subsystem options.

Note: This command only modifies the subsystem options. To effectively configure the virtual shared disks, you must first unconfigure all the virtual shared disks, unload the device driver, and then reconfigure the shared disks.

You can use the System Management Interface Tool (SMIT) to run this command. To use SMIT, enter:

smit vsd_mgmt

and select the Set/Show Virtual Shared Disk Device Driver Operational Parameters option or the Update virtual shared disk Device Driver Node Parameters option.

Flags

-n

Specifies the node numbers of the nodes whose information you want this command to update, or ALL nodes in the RSCT peer domain. You can issue the command /usr/bin/lsclcfg to find out the node number of the node you are running on.

-a

Specifies the adapter name to be used for virtual shared disk communications with this node or nodes. You must specify ml0 as the adapter name.

-b

Specifies the smallest buddy buffer a server uses to satisfy a remote request to a virtual shared disk. This value must be a power of 2 and greater than or equal to 4096. The suggested value to use is 4096 (4 KB).

-x

The largest buddy buffer a server will use to satisfy a remote request. This value must be a power of 2 and greater than or equal to the min_buddy_buffer_size. The suggested value to use is 262144 (256 KB). This value must be the same on all nodes in the RSCT peer domain.

-s

This is the number of max_buddy_buffer_size buffers to allocate. The virtual shared disk device driver will have an initial size when first loaded, and then will dynamically allocate and reclaim additional space as needed. The suggested starting value for a 32-bit kernel is 128 256 KB buffers. The suggested value is 2000 256KB buffers.

Buddy buffers are only used on the servers. On client nodes you may want to set max_buddy_buffers to 1.

Note: The statvsd command will indicate if remote requests are queueing waiting for buddy buffers.

-M

Specifies the maximum message size in bytes for virtual shared disks. This value must not be greater than the maximum transmission unit (MTU) size of the network. The recommended values are:

61440 (60 KB) for a switch
8192 (8 KB) for jumbo frame Ethernet
1024 (1 KB) for 1500-byte MTU Ethernet

-f

Specifies that this command will force updates to virtual shared disk subsystem options by reconfiguring one or more virtual shared disks on all nodes in the RSCT peer domain on which virtual shared disks are currently configured.

-c cluster_name | NONE

Changes the cluster the node belongs to. NONE removes the node from the cluster.

Note: The cluster_name is required only for SSA (Serial Storage Architecture) disks.

Parameters

vsd_name: Specifies the virtual shared disk whose underlying logical volume you no longer want to be globally accessed by any virtual shared disk nodes.

Security

You must have root authority to run this command.

Exit Status

0: Indicates the successful completion of the command.
nonzero: Indicates that an error occurred.

Restrictions

You must issue this command from a node that is online in the peer domain. To bring a peer domain online, use the startrpdomain command. To bring a particular node online in an existing peer domain, use the startrpnode command. For more information on creating and administering an RSCT peer domain, refer to RSCT Administration Guide.

Examples

To increase the buddy buffer size to 48 maximum sized buddy buffers on node 3, enter:

updatevsdnode -n 3 -s 48

Note: The device driver must be unconfigured from the kernel and reloaded to have this change go into effect.

Location

/opt/lpp/vsd/bin/updatevsdnode