In this scenario:
A local Zimbra server which has all mailboxes. It is MX10.
We want to install another server in other location (in a ISP) with zimbra but would run when the local zimbra fail only. This secondary Zimbra server is MX20 and this has not mailboxes. So when the primary or local Zimbra fail then the messages are stored in the secondary Zimbra. When the primary Zimbra fail-back then both are syncronized through VPN IPSec.
If I install a Zimbra MTA server and the connection between servers fail, this server can store messages temporary?.
Thank in advance.