Configure Zimbra Proxy for Kerberos Authentication If you use the Kerberos5 authenticating mechanism, you can configure it for the IMAP and POP proxy. Note: Make sure that your Kerberos5 authentication mechanism is correctly configured. See Zimbra LDAP Service, Kerberos5 Authentication Mechanism. 1. On each proxy node, set the zimbraReverseProxyDefaultRealm server attribute to the realm name corresponding to the proxy server. For example: zmprov ms [DNS name.isp.net] zimbraReverseProxyDefaultRealm [ISP.NET] 2. Each proxy IP address where email clients connect must be configured for GSSAPI authentication by the mail server. On each proxy node for each of the proxy IP addresses: zmprov mcf +zimbraReverseProxyAdminIPAddress [IP address] 3. On each proxy server: zmprov ms [proxyexample.net] zimbraReverseProxyImapSaslGssapiEnabled TRUE zmprov ms proxyl.isp.net zimbraReverseProxyPop3SaslGssapiEnabled TRUE 4. Restart the proxy server zmproxyctl restart
