I am doing the migration of mail servers Zimbra Zimbra, version 6 to 8.

When I do the migration of contacts and calendars, export happens smoothly on the source server, however, the target server when I run the command to import the following error occurs:

# /opt/zimbra/bin/zmmailbox -z -m <account> postRestURL -u http://server "Calendar?fmt=ics" /tmp/user-calendar.ics
[] INFO: I/O exception (java.net.ConnectException) caught when processing request: Connection refused
[] INFO: Retrying request
ERROR: remote.CONNECT_FAILURE (https://servidor:7071/service/admin/soap/) (cause: java.net.ConnectException Connection refused)

My structure has an LDAP server, a MailBox, an input MTA and an output MTA, all with the version ZCS-NETWORK-8.0.4

I executed several procedures, but none of them helped me to solution this problem.

Someone already faced this kind of problem and managed to solve it?