Sorry if this is basic. Line with an S7-1500, CPU 1515-2 PN and four ET200SP stations, TIA Portal V17. From the engineering room PC I can go online with the CPU on 10.20.5.10 no bother, but Accessible devices in TIA shows only my own PC's card, and PRONETA finds nothing at all. Ping to all four IMs works. I've a new IM 155-6 PN to name and I can't see it to do it, so I've lost a day on it already. I turned the Windows firewall off and checked I'd got the right network card in PRONETA, no change either way. Someone here reckoned the names in the project might be wrong so nothing lists, not sure I believe that. Engineering room is 10.20.100.x, the line is 10.20.5.x, if that matters. Does a browse like that even get from 10.20.100 to 10.20.5, or do I need to take the laptop down to the line panel?
It matters. Different subnets means there's a router sat between you and the line. What switch is it, and where does the engineering PC plug in?
A Scalance in the main cabinet, and IT says the engineering VLAN is routed to the line VLAN on it. The PC's on a wall port in the office, a standard IT socket I think. what is DCP? I saw it in the PRONETA settings and didn't want to touch anything.
DCP is Discovery and Configuration Protocol, the PROFINET service that lists devices and hands out names and IP addresses. It rides on plain Ethernet frames with no IP in them, so it only ever reaches devices in the same layer 2 segment. A router won't forward it. That's why you can go online with the CPU over IP from the office while accessible devices sits empty, they're two different mechanisms. Names aren't your problem. The empty list is.
Take the laptop to the line cabinet, plug into the same switch as the IMs, Update accessible devices, assign the name. After that, online from the office over IP works again. PROFINET System Description, addressing chapter. There's a writeup on this here: https://plctr.com/advanced-plc-networking-and-communication-protocols/
Took the laptop down to the line cabinet, plugged into a free port on the Scalance there, and PRONETA had all four IMs and the CPU listed straight away. Assigned the name to the new IM, it went green.
One more thing. Is it the firewall on the router blocking DCP, so IT could open it for me?