Hardware manual

Group Administration Group members
6–11
Requirement: You must use a default gateway to enable communication outside the local network.
1. Click
Group, then expand Members, then select the member name, and then click the Network tab.
2. In the IP Configuration panel next to the Default gateway field, click Modify.
3. Specify a default gateway IP address if you want to use a default gateway, or delete the IP address if you do not
want to use a
default gateway.
4. Click
OK.
Modifying a member name or description
Requirement: Member names must be unique in a group. A member name can consist of one to 63 letters,
numbers, or hyphens. The first character must be a letter or number. A member description can be
up to 127 alphanumeric characters.
1. Click
Group, then expand Members, then select the member name, and then click Modify member
settings.
2. In the Modify Member Settings dialog box, modify the member name or specify a description for the member.
3. Click
OK.
About write cache operations
Each (active) control module contains a battery-backed cache. The active control module cache operates in one of
two modes:
• Write-back – The member stores data in the cache until it is writt
en to disk drives, which can improve
performance. The cache battery protects the data in the cache. In a dual control module configuration, the
member mirrors cache data across the two controllers, providing additional data protection.
• Write-through – The member immediately writes data to the disk drives, whic
h might decrease performance.
You can set policies that control the mode when the battery is
low or a control module fails in a dual control
configuration. See Setting write cache policies.
Setting write cache policies
You can set policies that control the mode when the battery is low or a control module fails in a dual control
configuration.
Recommendation: Dell recommends that you keep the default write cache policy
settings for the best
performance and availability.
• Use write-through mode if only one controller is functi
onal – Also called single-controller-safe mode, if you
enable this policy on a member with a single control module, the cache always uses write-through mode. If you
disable this policy (the default), under non-failure conditions, the cache uses write-back mode.
If you enable this policy on a member with dual control modules,
but only one module is functioning, the cache