Monitoring VHS Replication

There are several SVCMON UDCs that can be used to monitor VHS replication. CygNet recommends creating points for the following UDCs. SVCMON points can be created for your Source Service, your Replicated VHS Service(s), or for both your Source and Replicated VHS Service(s). These points can be created using the CygNet ServiceMon Administration utility. Replication info items can be viewed for the VHS on the Replication page of the CygNet Service Information dialog box.

Note: It is recommended that the SVCMON timer be set for no more than five seconds.

Source SVCMON Points

CygNet recommends creating the following SVCMON points for your source service.

Info Item	Nice Name	Definition	SVCMON UDC
CHANGE_QUEUE_GUID	Notify Queue GUID	This value indicates a randomly-generated globally unique identifier (GUID) that is used along with the change queue initialization time (CHANGE_QUEUE_INITED) to uniquely identify a change queue. A replicating service uses both the GUID and the change queue initialization time as part of the change queue pointer to the source. In a redundant environment with multiple replicating services this combination more accurately indicates when to do an incremental resync. Applies to DBS and VHS services only.	-
CHANGE_QUEUE_NEWEST	Latest Notify Record	A numeric value representing the ID (sequence number) of the most recent change added to the change queue. When replication is up to date, this value for the source service will match the REPL_LAST_SEQ value on the replicated service. Note: This info item is displayed on both the Replication page and the Service Specific (CAS, CVS, DBS, VHS) page.	SVMDBSSEQC
CHANGE_QUEUE_SIZE	Change Update Queue Size	The configured size of the service change queue. This is the number of changes the service will store to answer replication requests before expiring the oldest changes. Note: This info item is displayed on both the Replication page and the Service Specific (CAS, CVS, DBS, VHS) page.	SVMVHSCQSZ
QUEUE_WRAP_TIME	VHS Last Q Wraparound	The last time that the VHS change queue completely filled up. After filling up, the change queue will wrap to the beginning of write new changes on top of the oldest ones.	SVMVHSCQWR
VHS_ADD_NAME_CNT	VHS Add Name Count		SVMVHSANCH
VHS_ADD_VALUE_CNT	VHS Add Value Count		SVMVHSAVCH
VHS_CHANGE_FILE_STAT	VHS Change Q File Status		SVMVHSCQST
VHS_COMPLEX_SEGMENTS	VHS Complex Segment Cnt		SVMVHSCMPX
VHS_CURR_SEQ_NUM	VHS Current Sequence Num	The sequence number of the last change on the change queue. Deprecated in favor of CHANGE_QUEUE_NEWEST.	SVMVHSCSEQ
VHS_DELETE_NAME_CNT	VHS Delete Name Count		SVMVHSDNCH
VHS_DELETE_VALUE_CNT	VHS Delete Value Count		SVMVHSDVCH
VHS_OLDEST_SEQ_NUM	VHS Oldest Sequence Num		SVMVHSOSEQ
VHS_QUEUE_INIT_TIME	VHS Change Q Init Time	The value represents the timestamp when the change queue was first initialized. A change of this value indicates the source VHS’s change queue has been reinitialized and queued changes may have been lost. When replication is up to date, this value for the source VHS will match the REPL_SRC_CHG_Q_INIT value on the replicated VHS. For non-VHS services, the info item CHANGE_QUEUE_INITED represents the same value.	SVMVHSCQIN
VHS_QUEUE_WRAPS	VHS Change Q Wraps		SVMVHSCQNW
VHS_UPDATE_NAME_CNT	VHS Update Name Count		SVMVHSUNCH
VHS_UPDATE_VALUE_CNT	VHS Update Value Count		SVMVHSUVCH

Info Item

Nice Name

Definition

SVCMON UDC

CHANGE_QUEUE_GUID

Notify Queue GUID

This value indicates a randomly-generated globally unique identifier (GUID) that is used along with the change queue initialization time (CHANGE_QUEUE_INITED) to uniquely identify a change queue. A replicating service uses both the GUID and the change queue initialization time as part of the change queue pointer to the source. In a redundant environment with multiple replicating services this combination more accurately indicates when to do an incremental resync. Applies to DBS and VHS services only.

CHANGE_QUEUE_NEWEST

Latest Notify Record

A numeric value representing the ID (sequence number) of the most recent change added to the change queue. When replication is up to date, this value for the source service will match the REPL_LAST_SEQ value on the replicated service.

Note: This info item is displayed on both the Replication page and the Service Specific (CAS, CVS, DBS, VHS) page.

SVMDBSSEQC

CHANGE_QUEUE_SIZE

Change Update Queue Size

The configured size of the service change queue. This is the number of changes the service will store to answer replication requests before expiring the oldest changes.

Note: This info item is displayed on both the Replication page and the Service Specific (CAS, CVS, DBS, VHS) page.

SVMVHSCQSZ

QUEUE_WRAP_TIME

VHS Last Q Wraparound

The last time that the VHS change queue completely filled up. After filling up, the change queue will wrap to the beginning of write new changes on top of the oldest ones.

SVMVHSCQWR

VHS_ADD_NAME_CNT

VHS Add Name Count

SVMVHSANCH

VHS_ADD_VALUE_CNT

VHS Add Value Count

SVMVHSAVCH

VHS_CHANGE_FILE_STAT

VHS Change Q File Status

SVMVHSCQST

VHS_COMPLEX_SEGMENTS

VHS Complex Segment Cnt

SVMVHSCMPX

VHS_CURR_SEQ_NUM

VHS Current Sequence Num

The sequence number of the last change on the change queue. Deprecated in favor of CHANGE_QUEUE_NEWEST.

SVMVHSCSEQ

VHS_DELETE_NAME_CNT

VHS Delete Name Count

SVMVHSDNCH

VHS_DELETE_VALUE_CNT

VHS Delete Value Count

SVMVHSDVCH

VHS_OLDEST_SEQ_NUM

VHS Oldest Sequence Num

SVMVHSOSEQ

VHS_QUEUE_INIT_TIME

VHS Change Q Init Time

The value represents the timestamp when the change queue was first initialized. A change of this value indicates the source VHS’s change queue has been reinitialized and queued changes may have been lost. When replication is up to date, this value for the source VHS will match the REPL_SRC_CHG_Q_INIT value on the replicated VHS. For non-VHS services, the info item CHANGE_QUEUE_INITED represents the same value.

SVMVHSCQIN

VHS_QUEUE_WRAPS

VHS Change Q Wraps

SVMVHSCQNW

VHS_UPDATE_NAME_CNT

VHS Update Name Count

SVMVHSUNCH

VHS_UPDATE_VALUE_CNT

VHS Update Value Count

SVMVHSUVCH

Replicated SVCMON Points

CygNet recommends creating the following SVCMON points for your replicated VHS(s).

Info Item	Nice Name	Definition	SVCMON UDC
REPL_CHECK_INTERVAL	Repl Poll Secs	The interval (in seconds) that a replicated service will check the source change queue for new updates. If the service is not replicating REPL_CHECK_INTERVAL will respond with an empty string.	SVMVHSRINT
REPL_MESSAGE_ERRORS	Repl messaging errors	The number of replication messaging errors. (Applies only to first forwarded destination for VHS services.)	SVMREPMSGE
REPL_NETWORK_ERRORS	Repl network errors	Number of replication network messaging errors (Applies only to first forwarded destination for VHS services.)	SVMREPDCLE
REPL_SOURCE	Repl Source Service	The source service name from which the replicated service is requesting changes.	SVMVHSRSRC
REPL_SRC_CHG_GUID	Source Queue GUID	This value is only relevant for replicated services. The value indicates a randomly-generated globally unique identifier (GUID) that is used along with the source service's change queue initialization time (REPL_SRC_CHG_Q_INIT) to uniquely identify a change queue. A replicating service uses both the GUID and the change queue initialization time as part of the change queue pointer to the source. In a redundant environment with multiple replicating services this combination more accurately indicates when to do an incremental resync. Applies to DBS and VHS services only.	-
REPL_SRC_CHG_Q_INIT	Source Queue Init Time	This value is only relevant for replicated services. The value represents the timestamp when the source service’s change queue was first initialized. A change in this value indicates the source service’s change queue has been reinitialized and queued changes may have been lost. When this happens for the CAS, CVS, and DBS service types, a full resynchronization is performed by the replicated service. When replication is up to date, this value for the replicated service will match the CHANGE_QUEUE_INITED value on the source service. Note: This value and the REPL_SRC_CHG_GUID are used together to more accurately identify the change queue pointer in a redundant environment with multiple replicating services.	SVMVHSRPCT
VHS_REPL_APPLY_ERRS	Change commit errors	The number of errors encountered by a replicated service in committing received changes to its own database. The service log file will contain details about these errors.	SVMVHSRAER
VHS_REPL_FILE_STATUS	Replication file clean	The shutdown status of the replicated service’s ReplicationPersist.dat file.	SVMVHSRFST
VHS_REPL_LAST_SEQ	Last sequence number	This value is only relevant for replicated VHS. The value represents the ID of the last change queue entry retrieved from the source VHS and committed to the replicated VHS. When replication is up to date, this value for the replicated VHS will match the CHANGE_QUEUE_NEWEST value on the source VHS. For non-VHS services, the info item REPL_LAST_SEQ represents the same value.	SVMVHSRLSQ
VHS_REPL_LAST_TIME	Last change process time	The last time a replicated service committed replicated changes to its database.	SVMVHSRLTM
VHS_REPL_MISS_EVENTS	Missing changes events	The number of times a replicated service has requested a sequence number no longer supported by the source service due to wrapping. This indicates that the replicated service may have missed changes.	SVMVHSRMIS
VHS_REPL_MISS_SEQ_1	Miss event 1 sequence	The last sequence number a replicated service processed successfully before it discovered the next sequence is no longer supported by the source’s change queue.	SVMVHSRMS1
VHS_REPL_MISS_SEQ_2	Miss event 2 sequence	The last sequence number a replicated service processed successfully on the previous event where it discovered the next sequence is no longer supported by the source’s change queue.	SVMVHSRMS2
VHS_REPL_MISS_SEQ_3	Miss event 3 sequence	The last sequence number a replicated service processed successfully on the second previous event where it discovered the next sequence is no longer supported by the source’s change queue.	SVMVHSRMS3
VHS_REPL_MISS_TIME_1	Miss event 1 time	The last time a replicated service successfully processed changes before it discovered the next sequence is no longer supported by the source’s change queue.	SVMVHSRMT1
VHS_REPL_MISS_TIME_2	Miss event 2 time	The last time a replicated service successfully processed changes on the previous event where it discovered the next sequence is no longer supported by the source’s change queue.	SVMVHSRMT2
VHS_REPL_MISS_TIME_3	Miss event 3 time	The last time a replicated service successfully processed changes on the second previous event where it discovered the next sequence is no longer supported by the source’s change queue.	SVMVHSRMT3
VHS_REPL_NUM_CHANGES	Changes processed	The number of incremental changes received and committed by a replicated service.	SVMVHSRNCH

Info Item

Nice Name

Definition

SVCMON UDC

REPL_CHECK_INTERVAL

Repl Poll Secs

The interval (in seconds) that a replicated service will check the source change queue for new updates. If the service is not replicating REPL_CHECK_INTERVAL will respond with an empty string.

SVMVHSRINT

REPL_MESSAGE_ERRORS

Repl messaging errors

The number of replication messaging errors. (Applies only to first forwarded destination for VHS services.)

SVMREPMSGE

REPL_NETWORK_ERRORS

Repl network errors

Number of replication network messaging errors (Applies only to first forwarded destination for VHS services.)

SVMREPDCLE

REPL_SOURCE

Repl Source Service

The source service name from which the replicated service is requesting changes.

SVMVHSRSRC

REPL_SRC_CHG_GUID

Source Queue GUID

This value is only relevant for replicated services. The value indicates a randomly-generated globally unique identifier (GUID) that is used along with the source service's change queue initialization time (REPL_SRC_CHG_Q_INIT) to uniquely identify a change queue. A replicating service uses both the GUID and the change queue initialization time as part of the change queue pointer to the source. In a redundant environment with multiple replicating services this combination more accurately indicates when to do an incremental resync. Applies to DBS and VHS services only.

REPL_SRC_CHG_Q_INIT

Source Queue Init Time

This value is only relevant for replicated services. The value represents the timestamp when the source service’s change queue was first initialized. A change in this value indicates the source service’s change queue has been reinitialized and queued changes may have been lost. When this happens for the CAS, CVS, and DBS service types, a full resynchronization is performed by the replicated service. When replication is up to date, this value for the replicated service will match the CHANGE_QUEUE_INITED value on the source service.

Note: This value and the REPL_SRC_CHG_GUID are used together to more accurately identify the change queue pointer in a redundant environment with multiple replicating services.

SVMVHSRPCT

VHS_REPL_APPLY_ERRS

Change commit errors

The number of errors encountered by a replicated service in committing received changes to its own database. The service log file will contain details about these errors.

SVMVHSRAER

VHS_REPL_FILE_STATUS

Replication file clean

The shutdown status of the replicated service’s ReplicationPersist.dat file.

SVMVHSRFST

VHS_REPL_LAST_SEQ

Last sequence number

This value is only relevant for replicated VHS. The value represents the ID of the last change queue entry retrieved from the source VHS and committed to the replicated VHS. When replication is up to date, this value for the replicated VHS will match the CHANGE_QUEUE_NEWEST value on the source VHS. For non-VHS services, the info item REPL_LAST_SEQ represents the same value.

SVMVHSRLSQ

VHS_REPL_LAST_TIME

Last change process time

The last time a replicated service committed replicated changes to its database.

SVMVHSRLTM

VHS_REPL_MISS_EVENTS

Missing changes events

The number of times a replicated service has requested a sequence number no longer supported by the source service due to wrapping. This indicates that the replicated service may have missed changes.

SVMVHSRMIS

VHS_REPL_MISS_SEQ_1

Miss event 1 sequence

The last sequence number a replicated service processed successfully before it discovered the next sequence is no longer supported by the source’s change queue.

SVMVHSRMS1

VHS_REPL_MISS_SEQ_2

Miss event 2 sequence

The last sequence number a replicated service processed successfully on the previous event where it discovered the next sequence is no longer supported by the source’s change queue.

SVMVHSRMS2

VHS_REPL_MISS_SEQ_3

Miss event 3 sequence

The last sequence number a replicated service processed successfully on the second previous event where it discovered the next sequence is no longer supported by the source’s change queue.

SVMVHSRMS3

VHS_REPL_MISS_TIME_1

Miss event 1 time

The last time a replicated service successfully processed changes before it discovered the next sequence is no longer supported by the source’s change queue.

SVMVHSRMT1

VHS_REPL_MISS_TIME_2

Miss event 2 time

The last time a replicated service successfully processed changes on the previous event where it discovered the next sequence is no longer supported by the source’s change queue.

SVMVHSRMT2

VHS_REPL_MISS_TIME_3

Miss event 3 time

The last time a replicated service successfully processed changes on the second previous event where it discovered the next sequence is no longer supported by the source’s change queue.

SVMVHSRMT3

VHS_REPL_NUM_CHANGES

Changes processed

The number of incremental changes received and committed by a replicated service.

SVMVHSRNCH

Source and Destination SVCMON Points

CygNet recommends creating the following SVCMON points for both your source and replicated VHSs.

Info Item	Nice Name	Definition	SVCMON UDC
DISK_QUEUE_LENGTH	I/O Global Pending Reqs	The number of pending reads and writes to the disk on which the service's main data files reside. This corresponds to the Avg. Disk Queue Length Performance Monitor statistic for the PhysicalDisk you are monitoring (for example, 1C:, 1D:, etc.).	SVMADQLC
PRCNT_CPU_TIME	Service % CPU Usage	The average percent of CPU time dedicated to the service. Valid range 0% to 100%.	SVMPCTCPUT
TOT_DISK_QUE_LENGTH	I/O Global Tot Pend Reqs	The number of pending reads and writes to all the disks in the machine. This corresponds to the PhysicalDisk(_Total)\Avg. Disk Queue Length Performance Monitor disk queue length.	SVMADQLT

Info Item

Nice Name

Definition

SVCMON UDC

DISK_QUEUE_LENGTH

I/O Global Pending Reqs

The number of pending reads and writes to the disk on which the service's main data files reside. This corresponds to the Avg. Disk Queue Length Performance Monitor statistic for the PhysicalDisk you are monitoring (for example, 1C:, 1D:, etc.).

SVMADQLC

PRCNT_CPU_TIME

Service % CPU Usage

The average percent of CPU time dedicated to the service. Valid range 0% to 100%.

SVMPCTCPUT

TOT_DISK_QUE_LENGTH

I/O Global Tot Pend Reqs

The number of pending reads and writes to all the disks in the machine. This corresponds to the PhysicalDisk(_Total)\Avg. Disk Queue Length Performance Monitor disk queue length.

SVMADQLT