HP NonStop G-Series - Manual (Page 128)

Nomadic Disk Manager Interface
ServerNet Nomadic Disk (Release 2) User’s Guide — 523968-001
7 -8
GIVE Command
Considerations
•
If a GIVE command does not contain the SEGMENT option, nor the DATA option, it
works on the current segment. If a current segment has not been set with the
ASSUME command, the last segment defined in the configuration file becomes the
assumed segment. If that segment is a DATA segment, issuing a GIVE command
has the same effect as issuing a GIVE DATA command. If that segment is a
SPARE segment, the GIVE command works only on that segment. Even though
SPARE segments are not directly supported, the code still allows them. Therefore,
you should always issue a GIVE DATA command rather than a simple GIVE
command.
•
In a planned switchover, you should issue the GIVE command on the owning node
before issuing a TAKE command on the destination node. The GIVE command
allows a smooth switchover. However, a GIVE command is not strictly necessary
and might not always be possible in an emergency; for example, if the giving node
is down. A TAKE command is always necessary, even if the GIVE command
finishes properly.
•
In a ServerNet Nomadic Disk environment, all data segments must be owned by
the same node. Therefore, whenever a data segment is given away, all data
segments are given away unless explicit instructions indicate otherwise.
•
The GIVE command implicitly performs a DOWN VOLUMES command. Before a
segment can be given away, all volumes on that segment must be stopped. Then,
all paths for that segment are switched to the NOT OWNED state. The GIVE
command performs this sequence for each segment that is to be given away.
•
The results of each intermediate step of a GIVE operation are written to the
Nomadic Disk Manager’s output file. For the GIVE command, the steps are:
1. Stops the volumes
2. Switches paths to NOT OWNED
Examples
ND> GIVE SEGMENT ONE,ONLY
ND> GIVE DATA
ND> GIVE