## Large SAN storage 

In larger SAN storage environments where multiple servers access many storage devices, such as IBM System Storage™ DS devices, through SAN switches, there are dedicated SAN administrators who manage disk resources. But from an AIX perspective, systems administrators can help by doing things like choosing multiple dual-port Fibre Channel (FC) cards to communicate with different fabrics and improve throughput. 

## 7.1.5 LVM configuration 

With LVM, you can mirror VGs, define a logical volume, and remove a disk with the system running. 

## Mirroring a logical volume 

The following scenarios explain how to mirror a normal VG. 

The following instructions show you how to mirror a root VG by using the System Management Interface Tool (SMIT): 

1. Select a VG in the Volumes container, and then choose Mirror  from the Selected  menu. Experienced administrators can use the mirrorvg  command. 

2. With root authority, add a disk to the VG by using the SMIT fast path that is shown in Example 7-1. 

# smitty extendvg Add a Physical Volume to a Volume Group Type or select values in entry fields. Press Enter AFTER making all desired changes. [Entry Fields]  FORCE the creation of volume group? no + * VOLUME GROUP name [] + * PHYSICAL VOLUME names [] + 

3. Mirror the VG on to the new disk by using the SMIT fast path that is shown in Example 7-2. 

# smit mirrorvg Mirror a Volume Group Type or select a value for the entry field. Press Enter AFTER making all desired changes. [Entry Fields] * VOLUME GROUP name [] + 

4. In the first panel, select a VG for mirroring. In the second panel, define the mirroring options or accept the defaults. 

