You should be able to execute 'show run' on the gateway and see the gateway running configuration.
Near the top, if it's been defined in your config, then you'll see:
'ip host mediaserver x.y.z.w'
'ip host mediaserver-backup a.b.c.d'
If you see something else like 'ip host media x.y.z.w' - then you'd assign the word 'media' to the user.microapp.media_server variable in the ICM Routing Script.
If you don't see the above, then go into 'en' and 'config t' mode and just enter the lines above (without the quotes) and test it out. If it works, remember to save it by executing 'wr mem'
Thank you so much. Can you please share me the link or document that talks about the Voice gateway basic understanding, configuration etc etc...
Thanks,
Gopal.