I came along with one whm/cpanel VPS for many years but want to start to escape the VPS failures or network blackouts that happen occasionlly. So I got a secondary VPS with the same features and now I slowly start learning to increase data availability combining both systems.
My main servers /home directory is rsynched to the second VPS once a day during off-peak time. /home includes webspace, mails, mail accounts, etc. Further, I have an IP-based DNS failover system that redirects http (port 80) requests to its corresponding (rsynced) IP on VPS-2. Clients are informed that they shall not ftp changes to their webspace otherwise it will be lost when we return to VPS-1
My question is regarding eMail services. I would like to offer my clients the possibility to use VPS-2 as mailserver for incoming mail as well as for outgoing mail during a downtime. In case they do not use VPS-2 mails should go to VPS-1 as soon as it becomes available again. I have entered a higher value MX record into the DNS of VPS-2, so mails go to VPS-2 and will be stored there until VPS-1 comes back online.
domain.com. 86400 IN MX 10 mail.domain.com. [this is VPS-1]
domain.com. 86400 IN MX 15 mail2.domain.com. [this is VPS-2]
I have chosen the whm/cpanel DNS feature "MX backup - configure server as a backup mail exchanger. Mail will be held until a lower number mail exchanger is available". I hope that clients can also retrieve mail from there during VPS-1 failures.
Now I am asking those who already tried to achieve something similar: Do you see anything missing with this setting, any drawbacks, did I overlook something essential, into which problems will I probably run?
My main servers /home directory is rsynched to the second VPS once a day during off-peak time. /home includes webspace, mails, mail accounts, etc. Further, I have an IP-based DNS failover system that redirects http (port 80) requests to its corresponding (rsynced) IP on VPS-2. Clients are informed that they shall not ftp changes to their webspace otherwise it will be lost when we return to VPS-1
My question is regarding eMail services. I would like to offer my clients the possibility to use VPS-2 as mailserver for incoming mail as well as for outgoing mail during a downtime. In case they do not use VPS-2 mails should go to VPS-1 as soon as it becomes available again. I have entered a higher value MX record into the DNS of VPS-2, so mails go to VPS-2 and will be stored there until VPS-1 comes back online.
domain.com. 86400 IN MX 10 mail.domain.com. [this is VPS-1]
domain.com. 86400 IN MX 15 mail2.domain.com. [this is VPS-2]
I have chosen the whm/cpanel DNS feature "MX backup - configure server as a backup mail exchanger. Mail will be held until a lower number mail exchanger is available". I hope that clients can also retrieve mail from there during VPS-1 failures.
Now I am asking those who already tried to achieve something similar: Do you see anything missing with this setting, any drawbacks, did I overlook something essential, into which problems will I probably run?