SSH Canonicalization

CanonicalDomains example.com example.net example.org
# CanonicalizeFallbackLocal no
CanonicalizeHostname yes

Host *.example.com
    IdentityFile ~/.ssh/exampleCOM
    User foo
Host *.example.net
    IdentityFile ~/.ssh/exampleNET
    User foo
Host *.example.org
    User foo
    IdentityFile ~/.ssh/exampleORG

more info: https://dotfiles.tnetconsulting.net/articles/2016/0109/ssh-canonicalization.html