I defined a voice port and dial peer for an fxs port that has an analog phone set plugged into it. The analog phone can call the ip phones but not the other way. What should my config look like for this to work? Thanks
Reset your UC520 back to factory default - you should be able to call back and forth between the IP phones and analog phones (do not need to add a dial peer etc). The analog phones are extensions 301 to 304 depending on which port you plug into.
On why it does not work now - see if you can try using an destination-pattern on the POTS dial peer of 321 to 324 (instead of 2xx or 301 - 304) - it maybe that you have multiple options to route calls to specific extensions (can confirm after seeing your config).
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