How to take mailbox backup of Zimbra Account from CLI

Mailbox backup from CLI Zimbra
Create a directory where you want to take backup
# chmod 777 /backup
or,
#chown zimbra.zimbra /backup

Login from zimbra user and run below command to Export/Backup user mailbox
Export/backup Zimbra mailbox 
#su - zimbra
$ zmmailbox -z -m user@example.com getRestURL "//?fmt=tgz" > /backup/user@example.com.tar.gz

Restore/Import Zimbra Mailbox backup

$ zmmailbox -z -m user@example.com postRestURL "//?fmt=tgz&resolve=reset" /backup/user@example.com.tar.gz

Note: You can change username and backup location as per your setup .