Multiple SASL servers
Hi, all, sorry if this has been asked before, I browsed the archives and could not find this mentioned. Running Postfix 2.8.6. I'm planning to use the Dovecot SASL implementation. Is there a way to define multiple Dovecot servers to achieve redundancy and to prevent problems in case one Dovecot server / process is down? /rolf
Re: Multiple SASL servers
Rolf E. Sonneveld: Hi, all, sorry if this has been asked before, I browsed the archives and could not find this mentioned. Running Postfix 2.8.6. I'm planning to use the Dovecot SASL implementation. Is there a way to define multiple Dovecot servers to achieve redundancy and to prevent problems in case one Dovecot server / process is down? At this time, multiple servers would require inet:host:port where host resolves to multiple IP addresses. /etc/postfix/main.cf: smtpd_sasl_path = inet:host:port I recall that Linux won't allow you to do that with /etc/hosts, so you'll have to use DNS or *BSD. Wietse
Re: Multiple SASL servers
On 12/14/11 1:00 PM, Wietse Venema wrote: Rolf E. Sonneveld: Hi, all, sorry if this has been asked before, I browsed the archives and could not find this mentioned. Running Postfix 2.8.6. I'm planning to use the Dovecot SASL implementation. Is there a way to define multiple Dovecot servers to achieve redundancy and to prevent problems in case one Dovecot server / process is down? At this time, multiple servers would require inet:host:port where host resolves to multiple IP addresses. Do you mean by this that, in a round robin setup like: auth.example.comINAauth1.example.com auth.example.comINAauth2.example.com and: /etc/postfix/main.cf: smtpd_sasl_path = inet:auth.example.com:port Postfix would try automatically auth2.example.com when it discovers auth1.example is down (in case it gets auth1.example.com,auth2.example.com (in this order) from the DNS resolver)? /etc/postfix/main.cf: smtpd_sasl_path = inet:host:port I recall that Linux won't allow you to do that with /etc/hosts, so you'll have to use DNS or *BSD. Thanks, /rolf
Re: Multiple SASL servers
Rolf E. Sonneveld: On 12/14/11 1:00 PM, Wietse Venema wrote: Rolf E. Sonneveld: Hi, all, sorry if this has been asked before, I browsed the archives and could not find this mentioned. Running Postfix 2.8.6. I'm planning to use the Dovecot SASL implementation. Is there a way to define multiple Dovecot servers to achieve redundancy and to prevent problems in case one Dovecot server / process is down? At this time, multiple servers would require inet:host:port where host resolves to multiple IP addresses. Do you mean by this that, in a round robin setup like: auth.example.comINAauth1.example.com auth.example.comINAauth2.example.com auth.example.comINA1.2.3.4 auth.example.comINA1.2.3.5 and: /etc/postfix/main.cf: smtpd_sasl_path = inet:auth.example.com:port Postfix would try automatically auth2.example.com when it discovers auth1.example is down (in case it gets auth1.example.com,auth2.example.com (in this order) from the DNS resolver)? The Postfix routine that makes a TCP connection will try each IP address (that the getaddrinfo() system routine returns for the hostname) and will stop when the connection succeeds, or when there are no more IP addresses. I'm betting that your getaddrinfo() will return multiple addresses with lookups from DNS. It appears that Linux handles that. Wietse /etc/postfix/main.cf: smtpd_sasl_path = inet:host:port I recall that Linux won't allow you to do that with /etc/hosts, so you'll have to use DNS or *BSD. Thanks, /rolf
Re: Multiple SASL servers
On 12/14/11 2:55 PM, Wietse Venema wrote: Rolf E. Sonneveld: On 12/14/11 1:00 PM, Wietse Venema wrote: Rolf E. Sonneveld: Hi, all, sorry if this has been asked before, I browsed the archives and could not find this mentioned. Running Postfix 2.8.6. I'm planning to use the Dovecot SASL implementation. Is there a way to define multiple Dovecot servers to achieve redundancy and to prevent problems in case one Dovecot server / process is down? At this time, multiple servers would require inet:host:port where host resolves to multiple IP addresses. Do you mean by this that, in a round robin setup like: auth.example.comINAauth1.example.com auth.example.comINAauth2.example.com auth.example.comINA1.2.3.4 auth.example.comINA1.2.3.5 Oops, excuse me, of course A records point to IP addresses. and: /etc/postfix/main.cf: smtpd_sasl_path = inet:auth.example.com:port Postfix would try automatically auth2.example.com when it discovers auth1.example is down (in case it gets auth1.example.com,auth2.example.com (in this order) from the DNS resolver)? The Postfix routine that makes a TCP connection will try each IP address (that the getaddrinfo() system routine returns for the hostname) and will stop when the connection succeeds, or when there are no more IP addresses. Great! I'm betting that your getaddrinfo() will return multiple addresses with lookups from DNS. It appears that Linux handles that. Yep, thanks, /rolf
