When you configure an internal or external GAL, a GAL sync account is automatically created for each domain. The address book in the galsync account is where the LDAP contact data is sync'd. Syncing the LDAP to this account gives users faster access to the GAL data and makes it easier for them to search the GAL.
If Both is selected, a GAL sync account is created for each LDAP data source. These accounts display in the administration console's Accounts list.
The internal GAL polling interval for the account determines how often the GAL sync account syncs with the LDAP server. The sync intervals can be in x days, hours, minutes or seconds.
When the GAL sync account syncs to the LDAP server the first time, all GAL contacts from the LDAP are added to the galsync account's address book. During subsequent syncs, the account is updated with information about new contact, modified contact, and deleted contact.
Do not modify the GAL sync account address book directly. When the LDAP syncs the GAL to the account, changes you make to the address book are deleted.