# Which IP group do I create?
**URL:** https://forum.networklessons.com/t/which-ip-group-do-i-create/12473
**Category:** Multicast
**Created:** [October 7, 2020, 12:00pm UTC](https://forum.networklessons.com/t/which-ip-group-do-i-create/12473 "2020-10-07T12:00:48Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@spellman\_p](https://forum.networklessons.com/u/spellman_p)
#### Post date: [October 7, 2020, 12:00pm UTC](https://forum.networklessons.com/t/which-ip-group-do-i-create/12473/1 "2020-10-07T12:00:48Z")
I have a question about the Multicast group creation and assignment. How do I know what group to make? I am trying to clean up a botched Multicast issue configuration and I am still pretty new to multicasting and your material has been great. But I have multiple groups showing up on my L3/L2 switches but no interfaces are assigned to a multicast group or an RP. I see you use 239.1.1.1, but I have 224.0.1.60, 239.1.0.1, 239.255.255.250/253/254 and 225.86.67.83, how do I know what group to create? Or if I add a groups 239.2.1.1 to an Interface will all Multicast address be assigned to that group?
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### Author:  [@lagapidis](https://forum.networklessons.com/u/lagapidis)
#### Post date: [October 8, 2020, 10:04am UTC](https://forum.networklessons.com/t/which-ip-group-do-i-create/12473/2 "2020-10-08T10:04:10Z")
Hello Patrick
This question has been answered here:
> [@Multicast Routing](https://forum.networklessons.com/t/multicast-routing/1330/29):
>
> Hello Patrick The multicast addresses that you can use are in the range of 224.0.0.0 to 239.255.255.255, but there are some reserved addresses within that range. The IP addresses you are using are all within the free for use ranges, except for 224.0.1.60 which is a well known multicast address registered as hp-device-disc as seen from the IANA address. Without researching it further, it is likely used by a service on an HP network device. Now having said that, how do you know what groups to …
Laz