Method and apparatus for replicating the punch command

摘要

The punch command may be replicated in a replication environment including a production site and a replication site. The solution includes implementing a punch command to free storage received at a replication site in a replication environment by applying the punch command to storage at the replication site and writing data being freed from the storage at the replication site to an undo stream of a journal at the replication site. If the punch command is not supported, a command to write zeros may be used. Further, an unpunch command is provided for properly undoing a punch command and storing data written to the volume before the punch command freed the storage. Additionally, large punch commands may be split into a plurality to smaller punch commands for efficient journal management. Additionally, volume space may be reclaimed by writing a punch command to the journal instead of zeros.

主权项

1. A computer-implemented method comprising:
intercepting a punch command by a splitter at a production site; sending the punch command from the splitter at the production site to a data protection appliance at the production site to free data from storage at the production site; determining whether the data protection appliance at the production site supports the punch command, and;
if the data protection appliance at the production site supports the punch command, processing the punch command by the data protection appliance at the production site to free data from the storage at the production site;if the data protection appliance at the production site does not support the punch command, notifying the splitter by the data protection appliance at the production site which, in turn, sends a write zero command to write zeros to a portion of the storage at the production site indicated by the punch command; sending the punch command from the data protection appliance at the production site to a data protection appliance at a replication site regardless of whether the data protection appliance at the replication site supports the punch command; receiving, at the data protection appliance at the replication site, the punch command sent from the data protection appliance at the production site; writing the punch command by the data protection appliance at the replication site to a journal at the replication site; applying, by the data protection appliance at the replication site, the punch command to storage at the replication site, the punch command applied by the data protection appliance at the replication site in response to the punch command received from the data protection appliance at the production site by determining whether the data protection appliance at the replication site supports the punch command, and:
if the data protection appliance at the replication site supports the punch command, processing the punch command by the data protection appliance at the replication site by sending the punch command to the storage at the replication site to free data from the storage at the replication site;if the data protection appliance at the replication site does not support the punch command, sending a write zero command to write zeros to a portion of the storage at the replication site indicated by the punch command; and writing data being freed or written as zeros from the storage at the replication site to an undo stream of the journal at the replication site.