Grid members can use database replication to maintain up-to-date zone data sets, so the secondary servers in the Grid can keep their zone data synchronized even if the primary server fails. Any external secondary servers can fall out of sync, however, if they rely only on the primary server to send notify messages when there is new zone data. Therefore all authoritative name servers in a Grid (all primary and secondary servers) send notify messages to external secondary servers by default. This ensures that an external secondary name server receives notify messages when its master primary server is a secondary name server in a Grid. However, it also increases the number of notify messages.
Infoblox recommends that you do not configure a large number of external secondary servers in stealth mode. To ensure that these secondary servers receive notifications about zone updates, you can allow zone transfers for these IP addresses and then enable the appliance to add them to the also-notify statement. For information about how to configure this feature, see Configuring Zone Transfers.
To specify whether secondary name servers in the Grid are to send notify messages to external secondary name servers:
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