Port 1587 (pra-elmd, pra_elmd)

IANA assigns port 1587 to pra-elmd, pra_elmd: pra_elmd IANA assigned this well-formed service name as a replacement for "pra_elmd"..

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference

pra-elmd TCP pra_elmd IANA assigned this well-formed service name as a replacement for "pra_elmd". Dennis Mastin -

pra_elmd TCP pra_elmd
This entry is an alias to "pra-elmd". This entry is now historic, not usable for use with many common service discovery mechanisms. Dennis Mastin -

pra-elmd UDP pra_elmd IANA assigned this well-formed service name as a replacement for "pra_elmd". Dennis Mastin -

pra_elmd UDP pra_elmd
This entry is an alias to "pra-elmd". This entry is now historic, not usable for use with many common service discovery mechanisms. Dennis Mastin -

Check what is listening on port 1587

Linux: is anything listening on TCP 1587?

sudo ss -tlnp 'sport = :1587'

Linux: UDP 1587

sudo ss -ulnp 'sport = :1587'

Linux / macOS: which process owns the port

sudo lsof -nP -i :1587

Older Linux / BSD (net-tools)

sudo netstat -tlnp | grep ':1587 '

Windows (Command Prompt)

netstat -ano | findstr :1587

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 1587 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine

nc -vz -w 5 HOST 1587

From Windows

Test-NetConnection HOST -Port 1587

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

nc -vzu -w 5 HOST 1587

Block port 1587 in the firewall

ufw

sudo ufw deny 1587/tcp

iptables

sudo iptables -A INPUT -p tcp --dport 1587 -j DROP

nftables

sudo nft add rule inet filter input tcp dport 1587 drop

Windows Firewall

New-NetFirewallRule -DisplayName 'Block TCP 1587' -Direction Inbound -Protocol TCP -LocalPort 1587 -Action Block

ufw

sudo ufw deny 1587/udp