Difference between revisions of "Modbus TCP Port"
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(Created page with "<p>In a Linux system only root can bind a port < 1024. <br /> As for Modbus TCP the standard port is 502.<br /> In this case you will get the next failure at runtime start-...") |
Revision as of 06:29, 6 August 2013
In a Linux system only root can bind a port < 1024.
As for Modbus TCP the standard port is 502.
In this case you will get the next failure at runtime start-up: "Modbus TCP Bind socket failure, retrying...Permission denied"
Change the port to a port number > 1024
Or
Set the s-bit on the plc-executable (note: if you rebuild do this again on the new plc-executable)
If you are running a firewall: The following commands opens this port:
sudo iptables -A INPUT -p tcp --dport 502 -j ACCEPT
sudo iptables -A OUTPUT -p tcp --dport 502 -j ACCEPT
TBD:
sudo sh -c "iptables-save > /etc/iptables.rules"