Many: See comments inline...
Many Ayromlou wrote: > Hi, > > I just had a discussion with some of our Network guys and they have > asked me to see if there is a possible way to give them a list of IP > multicast addresses that AG venueservers use. They are trying to modify > the rendevous point on our router based on Multicast addresse ranges, > since a lot of these new "Ghost" like applications use multicast to > mirror disks across networks with wrong ttl's and hard coded IP > addresses that are not in the admin range. > > Anyways.....my question for the Venueserver Gurus :-).....Is there a > pattern to the way VV Servers allocate addresses?? By default, mcast addresses are allocated in the range 224.2.128.0/17, which you can see in the MulticastAddressAllocator.py code. The Argonne venue servers use these defaults. You could query this range for a particular server using VenueServerIW.GetBaseAddress and VenueServerIW.GetAddressMask, but you would need to be an admin on the server for the calls to succeed. .....I've noticed a > lot of 224.x.x.x and 233.x.x.x and I've also seen the ncsa page that > keeps track of some of them (https://agschedule.ncsa.uiuc.edu:443/ > venues.asp). Or better yet is there some way of querying the info from > the VV Server through some simple means? You can query a venue programmatically for its multicast addresses using the VenueIW.GetStreams method. I put together a script that does this here: http://www.mcs.anl.gov/~turam/AG/GetMcastAddresses.py Given a venue address, it will print the mcast addresses assigned to the venue. You could use this tool to crawl for mcast addresses; let me know if you're interested, since there are some authorization hurdles in the way of such crawling. I really don't want to > dedicate one of my students to sit there and click every single Venue > on all the servers out there to make a list. > > Thanks, > TTYL > Many > >
