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TCPSVD(1) User Commands TCPSVD(1)

tcpsvd - manual page for tcpsvd 1.31.1

tcpsvd [-hEv] [-c N] [-C N[:MSG]] [-b N] [-u USER] [-l NAME] IP PORT PROG

BusyBox v1.31.1 (2020-04-30 13:38:01 EDT) multi-call binary.

Create TCP socket, bind to IP:PORT and listen for incoming connections. Run PROG for each connection.

IP:PORT to listen on
Program to run
Change to user/group after bind
-c N
Up to N connections simultaneously (default 30)
-b N
Allow backlog of approximately N TCP SYNs (default 20)
-C N[:MSG]
Allow only up to N connections from the same IP: new connections from this IP address are closed immediately, MSG is written to the peer before close
Don't set up environment
Look up peer's hostname
Local hostname (else look up local hostname in DNS)

Environment if no -E: PROTO='TCP' TCPREMOTEADDR='ip:port' ('[ip]:port' for IPv6) TCPLOCALADDR='ip:port' TCPORIGDSTADDR='ip:port' of destination before firewall

Useful for REDIRECTed-to-local connections: iptables -t nat -A PREROUTING -p tcp --dport 80 -j REDIRECT --to 8080

TCPCONCURRENCY=num_of_connects_from_this_ip If -h: TCPLOCALHOST='hostname' (-l NAME is used if specified) TCPREMOTEHOST='hostname'

April 2020 Fidelix 1.0