View Full Version : IGMP: Block or alow?

07 Jan 2006, 17:21
I have an ADSL connection, and when I first connect to the internet, Outpost ask me if to block or alow Igmp. Should I alow or block?

07 Jan 2006, 21:35
Hello POS,
Some ISPs require IGMP to keep the internet connection alive, but some don't.
You could try blocking it and see what happens, and if all continues normally you have nothing to worry about. If your connection subsequently fails in any way you can then unblock it. If you are not sure about this, make a configuration backup before blocking that you can restore if necessary, so returning you to the configuration you had before the block.
I block ALL IGMP and ICMP, with only one exception, iTunes, which has a system rule which allows only this one application which doesn't run properly without it.
Sorry I can't give you a definitive reply, but it will depend on the requirements of your individual applications, your ISP's requirements, and your overall system configuration.

31 Jan 2006, 11:00
I'm new here, but have been reading most of the posting with great interest and I've got a question regarding the IGMP.
What happens if you've asked Outpost to block IGMP and sometime down the road you wish to cancel this (and there's no config backup - well not one that I can see)
How would one unblock IGMP..?

31 Jan 2006, 11:11
Hi rn5577
Easy :)
The only way to block it is by making a rule to block it, so you just go and edit that rule...
The rule is in System (or Global) rules, and it is the rule to block IP Protocols, open the rule in "edit" and simply uncheck IGMP, then save it.
Hope that helps,

31 Jan 2006, 12:27
Thanks nippauls,
will keep that bit information to one side, just in case any applications ask for the IGMP to be reinstated.

31 Jan 2006, 12:58
Personally I create a new rule or copy a rule and move that above the original. This allows one to keep that rule without changes. In this instance I would create a new rule and check IP then IGMP type, but I would then also check the remote host to whichever address it connects to.
The original block rule will block traffic to other remote sites if something attempts it.