Port 625 (dec-dlm, dec_dlm)

IANA assigns port 625 to dec-dlm, dec_dlm: DEC DLM IANA assigned this well-formed service name as a replacement for "dec_dlm"..

Well-known (system) port, 0-1023 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference

dec-dlm TCP DEC DLM IANA assigned this well-formed service name as a replacement for "dec_dlm". Rudi Martin 2 -

dec_dlm TCP DEC DLM
This entry is an alias to "dec-dlm". This entry is now historic, not usable for use with many common service discovery mechanisms. Rudi Martin 2 -

dec-dlm UDP DEC DLM IANA assigned this well-formed service name as a replacement for "dec_dlm". Rudi Martin 2 -

dec_dlm UDP DEC DLM
This entry is an alias to "dec-dlm". This entry is now historic, not usable for use with many common service discovery mechanisms. Rudi Martin 2 -

Check what is listening on port 625

Linux: is anything listening on TCP 625?

sudo ss -tlnp 'sport = :625'

Linux: UDP 625

sudo ss -ulnp 'sport = :625'

Linux / macOS: which process owns the port

sudo lsof -nP -i :625

Older Linux / BSD (net-tools)

sudo netstat -tlnp | grep ':625 '

Windows (Command Prompt)

netstat -ano | findstr :625

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 625 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine

nc -vz -w 5 HOST 625

From Windows

Test-NetConnection HOST -Port 625

UDP probe (no reply does not prove it is closed)

nc -vzu -w 5 HOST 625

Block port 625 in the firewall

ufw

sudo ufw deny 625/tcp

iptables

sudo iptables -A INPUT -p tcp --dport 625 -j DROP

nftables

sudo nft add rule inet filter input tcp dport 625 drop

Windows Firewall

New-NetFirewallRule -DisplayName 'Block TCP 625' -Direction Inbound -Protocol TCP -LocalPort 625 -Action Block

ufw

sudo ufw deny 625/udp