.TH MDB_COPY 1 "2017/07/31" "LMDB 0.9.90" .\" Copyright 2012-2021 Howard Chu, Symas Corp. All Rights Reserved. .\" Copying restrictions apply. See COPYRIGHT/LICENSE. .SH NAME mdb_copy \- LMDB environment copy tool .SH SYNOPSIS .B mdb_copy [\c .BR \-V ] [\c .BR \-c ] [\c .BR \-n ] [\c .BR \-v ] [\c .BI \-m \ module [\c .BI \-w \ password\fR]] .B srcpath [\c .BR dstpath ] .SH DESCRIPTION The .B mdb_copy utility copies an LMDB environment. The environment can be copied regardless of whether it is currently in use. No lockfile is created, since it gets recreated at need. If .I dstpath is specified it must be the path of an empty directory for storing the backup. Otherwise, the backup will be written to stdout. .SH OPTIONS .TP .BR \-V Write the library version number to the standard output, and exit. .TP .BR \-c Compact while copying. Only current data pages will be copied; freed or unused pages will be omitted from the copy. This option will slow down the backup process as it is more CPU-intensive. Currently it fails if the environment has suffered a page leak. .TP .BR \-n Open LDMB environment(s) which do not use subdirectories. .TP .BR \-v Use the previous environment state instead of the latest state. This may be useful if the latest state has been corrupted. .TP .BI \-m \ module Load the specified dynamic module to utilize cryptographic functions. This is required to operate on environments that have been configured with page-level checksums or encryption. .TP .BI \-w \ password Specify the password for an encrypted environment. This is only used if a cryptography module has been loaded. .SH DIAGNOSTICS Exit status is zero if no errors occur. Errors result in a non-zero exit status and a diagnostic message being written to standard error. .SH CAVEATS This utility can trigger significant file size growth if run in parallel with write transactions, because pages which they free during copying cannot be reused until the copy is done. .SH "SEE ALSO" .BR mdb_stat (1) .SH AUTHOR Howard Chu of Symas Corporation