Some of those have valid certificates
ircs=6667,6679,6697,9999 nmap -Pn -sV -p $ircs ssl.ircnet.ovh nmap -Pn -sV -p $ircs barjavel.freenode.net nmap -Pn -sV -p $ircs autrechose.evolu.net nmap -Pn -sV -p $ircs irc.oftc.net nmap -Pn -sV -p $ircs irc.efnet.nl openssl s_client -connect ssl.ircnet.ovh:6697 openssl s_client -connect barjavel.freenode.net:6697 openssl s_client -connect autrechose.evolu.net:6697 openssl s_client -connect irc.oftc.net:6697 openssl s_client -connect irc.efnet.nl:9999
other IRCnet server names
ssl.irc.atw-inter.net psychz.ssl.ircnet.ovh DNS:psychz.ssl.ircnet.ovh, DNS:ssl.cloak.ircnet.ovh, DNS:ssl.ircnet.ovh
other Freenode server names
chat.freenode.net
other Online/EvoluNET server names
irc.dedibox.fr irc.evolu.net irc.online.net 62.210.159.99 autrechose.evolu.net free-vitry.fr.eu.evolu.net online-dc2.fr.eu.evolu.net 62.210.156.11 autrement.evolu.net online-dc3.fr.eu.evolu.net
IRCnet https://www.ircnet.com/servers http://www.ircnet.info/servers http://irc.tu-ilmenau.de/all_servers/ http://www.irchelp.org/networks/servers/ircnet.html
Freenode https://freenode.net/kb/answer/chat https://netsplit.de/servers/?net=freenode
Dedibox / EvoluNET / Online https://documentation.online.net/en/dedicated-server/network/dedibox-network https://netsplit.de/networks/Evolu.NET/ https://www.evolu.net/?page=reseau&aff=status
EFNet http://www.efnet.org/?module=servers