ZRobocopy: Fast, Reliable File Syncing for Windows Administrators

Getting Started with ZRobocopy — Commands, Options, and Best Practices

What ZRobocopy is

ZRobocopy is a Windows command-line file copy and sync tool based on Robocopy, extended with additional features (e.g., improved logging, parallelism, richer filters, or simpler syntax). It’s used for reliable one-way replication, incremental backups, and mirroring directories while preserving file attributes and NTFS metadata.

Basic usage

Typical command structure:

ZRobocopy   [] [Options]

Examples:

• Mirror a folder:

ZRobocopy C:\Data D:\Backup /MIR /R:3 /W:5

• Copy only changed files:

ZRobocopy C:\Data D:\Backup /XO /E

Important options (commonly used)

• /MIR — Mirror a directory tree (equivalent to /E plus delete extra files in destination). Use with caution.
• /E — Copy subdirectories, including empty ones.
• /S — Copy subdirectories excluding empty ones.
• /R:n — Number of retries on failed copies (default often 1 million; set lower).
• /W:n — Wait time between retries in seconds.
• /XO — Exclude older files (skip files older in source vs. destination).
• /XN — Exclude newer files.
• /XX — Exclude extra files and directories (opposite of /MIR deletion behavior).
• /LOG: — Write detailed log to file (overwrites).
• /LOG+: — Append to log file.
• /MT[:n] — Multithreaded copy with n threads (speeds up many small files). Beware of high CPU/disk I/O.
• /COPY:flags — Control what to copy (D=Data, A=Attributes, T=Timestamps, S=Security, O=Owner, U=Auditing). Example: /COPY:DAT
• /SEC — Copy files with security (equivalent to /COPY:DATS).
• /Z — Restartable mode (useful over unstable networks).
• /ZB — Use restartable mode; if access denied, use backup mode.
• /FFT — Assume FAT file times (2-second granularity) for compatibility with some drives.
• /ETA — Show estimated time of arrival (completion).
• /MAXAGE:/MINAGE, /MAXLAD:/MINLAD — Age/LAST ACCESS filters.

Best practices

• Test with /L (list-only) first to preview actions without making changes.
• Start with small datasets to verify options (especially /MIR and deletion flags).
• Use /LOG or /LOG+ to record runs for auditing and troubleshooting.
• Limit retries (/R) and wait times (/W) to reasonable values for automation.
• Use /MT carefully; for large single-file copies it adds no benefit and can increase contention.
• Preserve NTFS metadata when permissions and auditing are needed: include /COPY:SOU (or /SEC).
• Schedule via Task Scheduler or scheduled job; ensure tasks run with an account that has needed permissions and network access.
• Protect against accidental deletions: avoid running /MIR directly on production until validated; consider /XO and /