HTCSnap Agent
The HTCSnap agent manages the replication relationship between the source and target arrays when running a fire drill. Configure the agent in the fire drill service group, in place of the HTC agent.
Agent Operations
The agent performs different functions depending on the fire drill configuration.
Operation
(Entry Point)
|
Description
|
|---|
online
|
- Suspends replication between the source and the target arrays, takes a local snapshot of the target LUN, resumes the replication between the arrays, and takes the fire drill service group online by mounting the snapshot.
- Suspends replication between the source and the target arrays, takes a local snapshot of the target LUN, and takes the fire drill service group online by mounting the target LUN.
|
offline
|
- Destroys the snapshot by synchronizing data between the target array and the device on which snapshot was taken.
- Resumes replication between the source and the target arrays. Once the data is synchronized between the two arrays, the snapshot of the target array is destroyed by synchronizing data between the target array and the device where snapshot was taken.
|
monitor
|
Verifies the existence of the lock file to make sure the resource is online.
|
clean
|
Restores the state of the LUNs to their original state after a failed online operation.
|
action
|
For internal use.
|
Resource Type Definition
type HTCSnap (
static keylist RegList = { MountSnapshot, UseSnapshot }
static keylist SupportedActions = { clearvm }
static str ArgList[] = { TargetResName, MountSnapshot, UseSnapshot,
RequireSnapshot, ShadowInstance }
str TargetResName
int ShadowInstance
int MountSnapshot
int UseSnapshot
int RequireSnapshot
temp str Responsibility
temp str FDFile
)
Attribute Definitions
| Required Attributes
|
Type-Dimension
|
Description
|
|---|
TargetResName
|
string-scalar
|
For HTC - Name of the resource managing the LUNs to be snapshotted. The target resource is of type HTC if the data being snapshot is replicated; the resource is of type DiskGroup if the data is not replicated.
For example, some applications like Oracle have data files and redo logs replicated, but temporary tablespace not replicated. The temporary tablespace must still exist at the DR site and may be part of its own disk group and is snapshotted independently.
|
ShadowInstance
|
integer-scalar
|
The instance number of the ShadowInstance P-VOL group.
Note The P-VOL group must include the same LUNs as either the TrueCopy S-VOL group (if snapshotting replicated data) or the same LUNs as in the VxVM disk group (if snapshotting non-replicated data).
|
UseSnapshot
|
integer-scalar
|
Specifies whether the HTCSnap resource takes a local snapshot of the target array. Set this attribute to 1 for Gold and Silver configurations. For Bronze, set this attribute to 0.
See Configuring the Snapshot Attributes.
|
RequireSnapshot
|
integer-scalar
|
Specifies whether the HTCSnap resource must take a snapshot before coming online.
Set this attribute to 1 if you want the resource to come online only after it succeeds in taking a snapshot.
Set this attribute to 0 if you do want the resource to come online even if it fails to take a snapshot. Setting this attribute to 0 creates the Bronze configuration.
Note Set this attribute to 1 only if UseSnapshot is set to 1.
|
MountSnapshot
|
integer-scalar
|
Specifies whether the resource uses the snapshot to bring the service group online. Set this attribute to 1 for Gold configuration. For Silver and Bronze configurations, set the attribute to 0.
Note Set this attribute to 1 only if UseSnapshot is set to 1.
|
| Internal Attributes
|
Type-Dimension
|
Description
|
|---|
Responsibility
|
temporary string
|
For internal use only.
Used by the agent to keep track of resynchonizing snapshots.
|
FDFile
|
temporary string
|
For internal use only.
Used by the agent to locate the latest fire drill report.
|
Configuring the Snapshot Attributes
The UseSnapshot, MountSnapshot, and RequireSnapshot attributes define the fire drill configuration.
| Attribute
|
Gold
|
Silver
|
Bronze
|
|---|
MountSnapshot
|
1
|
0
|
0
|
UseSnapshot
|
1
|
1
|
0
|
Setting the RequireSnapshot attribute to 0 enables a Gold or Silver configuration to run in the Bronze mode if the snapshot operation fails.
|
