Specifying destination systems on the source

How to specify destination systems on the source system

There are two methods of specifying destination systems on the source system:

You can specify the destination systems that are allowed access to the source system by using the snapmirror.access option. This option specifies which SnapMirror destination systems can initiate transfers, and which network interfaces they can use.This is the preferred method for controlling SnapMirror access on a SnapMirror source systems.
You can generate a snapmirror.allow file in the /etc/ directory on the source system. The /etc/snapmirror.allow file specifies the host names of storage systems that are allowed to copy data directly from the source system.
If the snapmirror.access option is set to legacy (the default setting), the snapmirror.allow file defines the access permissions.

Specifying destinations using the snapmirror.access option

To specify the SnapMirror destinations allowed access to the SnapMirror source using the snapmirror.access option, complete the following step.

Step	Action
1	On the source system, enter the following command: options snapmirror.access access_specification The syntax for specifying which systems are allowed access to the server is the same for SNMP, Telnet, and rsh, and is described in the na_protocolaccess(8) man page. For more information about the `options` command, see the na_options(1) man page. This option persists across reboots.

Step

Action

On the source system, enter the following command:

options snapmirror.access access_specification

The syntax for specifying which systems are allowed access to the server is the same for SNMP, Telnet, and rsh, and is described in the na_protocolaccess(8) man page. For more information about the options command, see the na_options(1) man page.

This option persists across reboots.

Example

If you want SnapMirror to copy data locally on systemA and to another system named systemB, enter the following at the prompt on systemA:

systemA> options snapmirror.access host=systemA,systemB

Specifying destinations using the snapmirror.allow file

To specify the SnapMirror destinations allowed access to the SnapMirror source using the /etc/snapmirror.allow file, complete the following steps.

Step	Action
1	If the snapmirror.allow file does not already exist, use a text editor to create a file called snapmirror.allow in the /etc directory on the root volume of the source system.
2	Add the name of each storage system to which you are replicating data, on its own line, to the /etc/snapmirror.allow file. You do not have to add the name of the local system.
3	Save edits to the file.

Example

If you want SnapMirror to copy data locally on systemA and to other systems named systemB and systemC, create a /etc/snapmirror.allow file on systemA with the following lines added:

systemB

systemC

Entries in the /etc/snapmirror.allow file are case-sensitive. You can use the hostname command on the destination system to find the correct format for each entry in the /etc/snapmirror.allow file.

Resolving host names to their IP addresses

By default, the SnapMirror feature checks host names in the /etc/snapmirror.allow file against the host name sent from the destination system. Alternatively, you can set SnapMirror to resolve the host names in the /etc/snapmirror.allow file to their IP addresses and compare them with the IP address of the destination system.

The snapmirror.checkip.enable option controls how the host names are checked. When the option is off, which is the default, the entries in the /etc/snapmirror.allow file must match the host name of the destination system reported by the hostname command. When the option is on, the source system resolves the names in the snapmirror.allow file to IP addresses and then checks for a match with the IP address of the requesting destination system. In this mode, literal IP addresses (for example, 123.45.67.89) and fully qualified names (for example, systemA.acme.com) can be valid entries in the /etc/snapmirror.allow file.

The /etc/snapmirror.allow file entry must map to the IP address of the originating network interface on the destination system. For example, if the request comes from the IP address of a Gigabit Ethernet interface e10 named systemA-e10, then the /etc/snapmirror.allow file must contain "systemA-e10" or "systemA-e10.acme.com" so the name resolves to the correct IP address.

A local SnapMirror relationship, between two volumes on the same storage system, does not require an entry in the /etc/snapmirror.allow file.

To configure SnapMirror to resolve host names to their IP addresses, complete the following step.

Step	Action
1	On the source system, enter the following command: options snapmirror.checkip.enable on