Hi Sipos,
it should certainly work with current osmo-msc. The cause looks like actually an MS is rejecting the connection. It is not an error report that i remember to have seen, so nothing in particular comes to mind.
Hence, yes, a pcap might help to understand what is going wrong for you. Also quite helpful would be at least the osmo-msc log with the 'codecs:' log lines that you get with 'logging level cc debug'.
BTW, 'mncc-int' is an old config item for internal MNCC and does not have much bearing on codec decisions, in neither external nor internal MNCC. As I am looking now, it seems to be entirely unused, actually.
BTW2, a detailed overview of codec decisions is shown in osmo-bsc/doc/codec_resolution.msc
~N
On Tue, Feb 04, 2025 at 06:53:21PM +0100, Sipos Csaba wrote:
Dear list,
FR calls between mobile phones are working fine, but when I change the codec-list to "codec-list fr2 fr1 fr3" or "codec-list fr3 fr1 fr2", I am getting a Remote Transcoder Failure:
lchan(0-0-1-TCH_F-0)[0x630d01c78b80]{ESTABLISHED}: (type=TCH_F) CONNECTION FAIL (cause=Remote Transcoder Failure [ 28 ])
In the BSC config: codec-support fr efr amr codec-list fr2 fr1 fr3
In the MSC config: mncc-int default-codec tch-f fr default-codec tch-h hr
Both the phones and the BTS is FR/EFR/AMR capable.
I am fairly sure with Osmo-NITB at least EFR was working with these phones and BTS some years ago.
If needed, I can provide a pcap.
If someone has an idea, please let me know.
Regards, Csaba