Google Apps Directory Sync Administration Guide - Manual (Page 97)

Configuration 97
Add Group Search Rule (Prefix-Suffix)
You may need Directory Sync to add a prefix or suffix to the value your LDAP
server provides for a mailing list’s email address or its members’ email addresses.
Specify any prefixes or suffixes here.
LDAP Group Rule Setting Description
Group Email Address Prefix Text to add at the beginning of a mailing list’s
email address when creating the
corresponding group email address.
Example: groups-
Group Email Address Suffix Text to add at the end of a mailing list’s email
address when creating the corresponding
group email address.
Example: -list
Invalid characters
replacement If a mailing list name in your LDAP server
contains any spaces or other invalid
characters, they will be replaced with this
character string.
If you leave this blank, Directory Sync removes
spaces and concatenates group names.
Example: underscore (_)