I am trying to setup a backup mail server that will be used if our primary server fails. The backup server is located in Site B, primary is in Site A. Site A is connected to Site B site through a VPN.
How can I make sure that when primary goes down, the backup at Site B, sends mail out using the gateway at Site A through the VPN. And vice-versa. When mail is sent to joe@company.com, the MX record for company.com is registered to the hosting provider at Site A. Therefore, the mail will be sent to the IP address at Site A.
To keep mail from bouncing because of MX records, the backup server needs to send from Site A's gateway where the MX record is associated with.
Using postfix is this possible? I'm having problems doing NAT translations and static routes.
How can I make sure that when primary goes down, the backup at Site B, sends mail out using the gateway at Site A through the VPN. And vice-versa. When mail is sent to joe@company.com, the MX record for company.com is registered to the hosting provider at Site A. Therefore, the mail will be sent to the IP address at Site A.
To keep mail from bouncing because of MX records, the backup server needs to send from Site A's gateway where the MX record is associated with.
Using postfix is this possible? I'm having problems doing NAT translations and static routes.