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CallManager 4.1(3) and VG248 - POS Problems


I have a VG248 where I have like 10 POS (point of sales equipment). Also I have the T1/PRIs in a CMM blade on a Catalyst 6500 switch where the PSTN resides. Customer is complaining that in order for the POS to complete a transaction they need to retry a lot and that wasn't happing in the old legacy PBX.

I configured the VG248 with fax-relay disable and also the cmm blade is using mgcp and I disable the T.38 fax relay in order for the connection to use fax-passthrough. Is there anything else I need to disable/enable in order to make it work fine. Also on the VG248 there are like 10-12 fax machines that are working fine using the same configuration.

Any ideas?



Re: CallManager 4.1(3) and VG248 - POS Problems

The POS terminals use modem protocols rather than fax (at least the ones I have worked with). You will have better performance if you change the VG248 port passthrough mode to passthrough only:ECAN disabled.

New Member

Re: CallManager 4.1(3) and VG248 - POS Problems

I will try that mode. And I don't need to change anything on the MGCP T1 endpoints that are connected to the CMM blade on a Catalyst 6500?

Thans in advanced,



Re: CallManager 4.1(3) and VG248 - POS Problems

Make sure the CMM has modem passthrough enabled:

mgcp modem passthrough voip mode nse

Also check to be sure that the T1s are running clean with no slips. Errors will impact modem calls more than voice.

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