Habilitamos el uso de los cdr_custom
nano /etc/asterisk/cdr_custom.conf
Modificando la linea [mappings], quitandole los comentarios
[mappings] calls.csv => ${CSV_QUOTE(${CDR(accountcode)})},${CSV_QUOTE(${CDR(src)})},${CSV_QUOTE(${CDR(dst)})},${CSV_QUOTE(${CDR(dcontext)})},${CSV_QUOTE(${CDR(clid)})},${CSV_QUOTE(${CDR(channel)})},${CSV_QUOTE(${CDR(dstchannel)})},${CSV_QUOTE(${CDR(lastapp)})},${CSV_QUOTE(${CDR(lastdata)})},${CSV_QUOTE(${CDR(start)})},${CSV_QUOTE(${CDR(answer)})},${CDR(billsec)},${CSV_QUOTE(${CDR(duration)})},${CSV_QUOTE(${CDR(end)})},${CSV_QUOTE(${CDR(disposition)})},${CSV_QUOTE(${CDR(amaflags)})},${CSV_QUOTE(${CDR(uniqueid)})},${CSV_QUOTE(${CDR(userfield)})}
Éstos archivos se guardan en la ruta /var/log/asterisk/cdr-custom/