Motorola DIMETRA MTS 2, Installation, Configuration And Basic Service Manual

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MTS 2 and MTS 4 Installation, Con
fi
guration and Basic Service Manual IP and Audio
If the counter labeled "Number of discards when disabled" is not zero, this indicates that frame relay
fragmentation is disabled on the Site Controller, but enabled on the remote equipment. If however, there are
non zero values for the counters labeled "Transmit Framed fragmented" and "Number of fragments transmitted"
but the counters labeled "Number of received fragments" and "Number of received frames" are zero, this
would indicate that the remote equipment has not been con
fi
gured for FRF.20 frame relay fragmentation.
IP and Audio
If - however - all is well with the site link, but there are issues with no uplink or downlink audio, the
likely culprits are either the con
fi
guration of the UDP port used for voice, the CRTP con
fi
guration
- or both. A quick check can be made for crtp activity by typing status crtp .
SC) status crtp
Compressed Frame Count 0
Decompressed Frame Count 99
Contexts Invalidated 1
Tx Context State Packets 0
Rx Context State Packets 0
Tx Full Header Packets 0
Rx Full Header Packets 1
Discards when disabled 0
If the compressed frame count is zero, check the con
fi
guration to determine if CRTP is - indeed
- enabled. If the decompressed frame count is zero, check the CRTP con
fi
guration on the core
router in order to ensure this is enabled, and not set to "passive"
If - however, the decompressed counter is non zero, it would indicate that the Site Controller is receiving
downlink audio, however - the packets are not getting processed for some other reason. It should then be
determined if the IP layer is discarding the received audio packets - this can be a result of not enabling
header extensions with CRTP on the core router. The command to use is
netstat -a .
The section of interest would be the UDP statistics:
UDP datagrams delivered to UDP users 14114
UDP datagrams received for unknown ports 234
UDP datagrams received with other errors 0
UDP datagrams sent from this entity 14117
Input datagrams received from interfaces 14364
Drops due to format errors 0
Drops due to invalid addresses 0
IP datagrams forwarded 0
IP datagrams discarded due to unknown protocol 0
Input datagrams discarded with no problems 0
Datagrams delivered to IP user-protocols 14364
6802800U74-N September 2009
13-15