recoverpacket

Resets epoch row table so changes in lost packets are resent

APPLICABILITY

SYNOPSIS

recoverpacket [ -c·omment comment | -cfi·le comment-file-pname | -cq·uery

| -cqe·ach | -nc·omment ] [ -sin·ce date-time ] replica-selector ...

DESCRIPTION

The recoverpacket command resets the epoch row at a sending replica to reflect the last synchronization sent to a receiving replica before a particular time. It scans through a list of epoch rows saved at the time of each export, looking for an entry prior to the time specified. When it finds an entry, it uses the associated row to reset the epoch row for the specified receiving replica. The next time a packet is sent, it includes the changes that were in the lost packet.

Resetting Epoch Numbers Automatically

When you send an update packet to another replica, success of the transport and import phases is assumed. Therefore, the sending replica's epoch number matrix is updated to reflect that the changes are made at the receiving replica. However, if the packet is lost before reaching the receiving replica, the sending replica's assumption that the receiving replica is up to date is incorrect.

The updated epoch numbers must be returned to the values they had before the packet was sent. Making these corrections to the sending replica's epoch number matrix causes it to include the same changes in the next update packet it sends to the receiving replica.

The administrator at the receiving replica must run an lshistory command to determine the time of the last successful import. The administrator at the sending replica uses this time in the recoverpacket command.

NOTE: If the two sites are not in the same time zone, or you do not send packets at the same time you generate them (for example, you generate packets at midnight and send them at 6:00 A.M.), you must adjust for the time difference.

Resetting Epoch Numbers Manually

If there are no saved epoch rows for the replica that are as old as the specified time, the recoverpacket command fails. In this case, the administrator at the receiving site must use the lsepoch command to determine the correct epoch number, and the administrator at the sending site must run chepoch on the sending replica to reset the epoch row. See the chepoch reference page for more information.

RESTRICTIONS

Identities: You must have one of the following identities:

• VOB owner

• root (UNIX)

• Member of the ClearCase administrators group (Windows)

Locks: An error occurs if one or more of these objects are locked: VOB.

Mastership: No mastership restrictions.

OPTIONS AND ARGUMENTS

EVENT RECORDS AND COMMENTS. Default: Creates one or more event records, with commenting controlled by the standard ClearCase user profile (default: -nc). See EVENT RECORDS AND COMMENTS in the multitool reference page. To edit a comment, use cleartool chevent.

-c·omment comment | -cfi·le comment-file-pname | -cq·uery | -cqe·ach | -nc·omment

Overrides the default with the specified comment option.

SPECIFYING THE TIME. Default: If the time is not specified, recoverpacket uses the current time (and, therefore, resets the epoch row so that the changes in the most recent update packet are resent).

-sin·ce date-time

Specifies the time of the last successful processing of a packet at the receiving site. The date-time argument can have any of the following formats:

date.time | date | time | now
where:

date	:=	day-of-week | long-date
time	:=	h[h]:m[m][:s[s]] [UTC [ [ + | - ]h[h][:m[m] ] ] ]
day-of-week	:=	today |yesterday |Sunday | ... |Saturday |Sun | ... |Sat
long-date	:=	d[d]-month[-[yy]yy]
month	:=	January |... |December |Jan |... |Dec

Specify the time in 24-hour format, relative to the local time zone. If you omit the time, the default value is 00:00:00. If you omit the date, the default value is today. If you omit the century, year, or a specific date, the most recent one is used. Specify UTC if you want the time to be resolved to the same moment in time regardless of time zone. Use the plus (+) or minus (-) operator to specify a positive or negative offset to the UTC time. If you specify UTC without hour or minute offsets, the default setting is Greenwich Mean Time (GMT). (Dates before January 1, 1970 Universal Coordinated Time (UTC) are invalid.)

Examples:

22-November-1990
sunday
yesterday.16:00
8-jun
13:00
today
9-Aug.10:00UTC

SPECIFYING THE ROW TO BE MODIFIED. Default: None.

replica-selector

Specifies the replica for which the epoch row is reset. Specify replica-selector in the form [replica:]replica-name[@vob-selector]

replica-name	Name of the replica (displayed with lsreplica)
vob-selector	VOB family of the replica; can be omitted if the current working directory is within the VOB. Specify vob-selector in the form [vob:]pname-in-vob
	pname-in-vob	Pathname of the VOB-tag (whether or not the VOB is mounted) or of any file-system object within the VOB (if the VOB is mounted)

EXAMPLES

• Reset the epoch row for replica sanfran_hub so that changes sent since last Monday will be included in the next packet that is sent.

multitool recoverpacket -nc -since Monday sanfran_hub

• Reset the epoch row for replica boston_hub so that the changes included in the most recent update packet will be included in the next packet that is sent.

multitool recoverpacket -c "send latest packet" boston_hub@\dev

• Determine the last successful import at replica bangalore, reset the epoch row at replica boston_hub, and send an update packet.

At replica bangalore:

cleartool lshistory replica:bangalore@\dev
19-Oct.15:36 smg import sync from replica "boston_hub" to replica "bangalore"
"Imported synchronization information from replica "boston_hub".
...

At replica boston_hub (remember to adjust for the time zone difference):

multitool recoverpacket -since 19-Oct.05:06 bangalore@/vobs/dev
Using epoch information from Monday 10/19/99 05:05:45
Epoch row for replica "bangalore" successfully reset.

multitool syncreplica -export -fship bangalore@/vobs/dev
Generating synchronization packet /usr/atria/shipping/ms_ship/outgoing/sync_boston_hub_22-Oct-99.15.44.28_48 96_1
- shipping order file is /usr/atria/shipping/ms_ship/outgoing/sh_o_sync_boston_hub_22-Oct-99.15.44. 28_4896_1
Attempting to forward/deliver generated packets...
-- Forwarded/delivered packet /usr/atria/shipping/ms_ship/outgoing/sync_boston_hub_22-Oct-99.15.44.28_48 96_1

SEE ALSO

chepoch, lsepoch, restorereplica
VOB Operations and the Oplog in Chapter 1, Introduction to MultiSite