Search notes:
/etc/services
/etc/services provies a mapping between friendly names for internet services and their corresponding port numbers and protocol types.
Selected portions of /etc/services might look like
# Network services, Internet style
#
# Updated from https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml .
…
ftp-data 20/tcp
ftp 21/tcp
…
ssh 22/tcp # SSH Remote Login Protocol
telnet 23/tcp
smtp 25/tcp mail
time 37/tcp timserver
time 37/udp timserver
whois 43/tcp nicname
…
http 80/tcp www # WorldWideWeb HTTP
kerberos 88/tcp kerberos5 krb5 kerberos-sec # Kerberos v5
kerberos 88/udp kerberos5 krb5 kerberos-sec # Kerberos v5
…
ldap 389/tcp # Lightweight Directory Access Protocol
ldap 389/udp
…
https 443/tcp # http protocol over TLS/SSL
https 443/udp # HTTP/3
…
microsoft-ds 445/tcp # Microsoft Naked CIFS
…
#
# UNIX specific services
#
exec 512/tcp
biff 512/udp comsat
login 513/tcp
who 513/udp whod
shell 514/tcp cmd syslog # no passwords used
syslog 514/udp
…
#=========================================================================
# The remaining port numbers are not as allocated by IANA.
#=========================================================================
# Kerberos (Project Athena/MIT) services
kerberos4 750/udp kerberos-iv kdc # Kerberos (server)
kerberos4 750/tcp kerberos-iv kdc
kerberos-master 751/udp kerberos_master # Kerberos authentication
kerberos-master 751/tcp
passwd-server 752/udp passwd_server # Kerberos passwd server
krb-prop 754/tcp krb_prop krb5_prop hprop # Kerberos slave propagation
…
git 9418/tcp # Git Version Control System