Hello everybody,

I seek information to configure sendmail:
- I have 2 server relay of mail, one is used as backup of the other. Is
it possible to configure sendmail in order to contact the server relail?
(If it does not manage to contact the first at the end of X second, it
contacts the second.)

thank you in advance.

I believe a secondary MX record can achieve this. (if I understand what
you are asking)

Otherwise, if you want an smtp client to try one relay first then
another, that will require the client to support such a feature in its
code.