scashell Posted July 17, 2007 Report Share Posted July 17, 2007 We have subnets 172.16.100.x and 102.x and so forth. When I try to add these subnets in retrospect, it defaults to 172.16.0.0 when I use the subnet mask of 255.255.0.0, which they are configured as. It wont accept the subnet mask I enter. On another network it works fine, ie. 10.64.32.x and 33.x with 255.255.255.0. I am no network guru admittedly, but is there a way for me to specify these subnets with the mask 255.255.0.0 in retrospect? I am running 7.5 windows. thanks oh, I should point out that I can add these clients via Direct method with no problems. Quote Link to comment Share on other sites More sharing options...
rhwalker Posted July 17, 2007 Report Share Posted July 17, 2007 The subnet mask is not arbitrary; it controls how the broadcast packets are interpreted, how routing is done, etc. It depends on how you have your network set up, and the entire subnet must agree on how it is set up. How do you have it set up? A subnet mask of 255.255.0.0 for Subnet 172.16.100.x and 172.16.102.x gives a network number of 172.16.0.0. Sounds like Retrospect is exhibiting the expected behavior. Do I misunderstand your statement of the problem? Are you aware of RFC-1597? RFC-1597 russ Quote Link to comment Share on other sites More sharing options...
scashell Posted July 17, 2007 Author Report Share Posted July 17, 2007 Your interpretation is correct. I dont believe this to be a retrsospect problem, but a config problem with our network. I am not allowed access to the routers and I doubt they will make any changes for this application. I'm really just trying to find a work around. Thanks you for any help you can provide. Quote Link to comment Share on other sites More sharing options...
rhwalker Posted July 17, 2007 Report Share Posted July 17, 2007 Are you saying that: (1) Your network has a subnet of 172.16.100.x with a subnet mask of 255.255.255.0 AND (2) Your network has a subnet of 172.16.102.x with a subnet mask of 255.255.255.0 and Retrospect won't let you enter a subnet mask of 255.255.255.0 ? Or are you saying that: (3) your network has a subnet of 172.16.x.x with a subnet mask of 255.255.0.0 ? If it is #3, then you DO NOT have subnets of 172.16.100.x and 172.16.102.x, but instead have a single subnet of 172.16.x.x. Perhaps I don't understand the problem. I don't see any config problem with your network, just that it doesn't have the subnets you think it has. Russ Quote Link to comment Share on other sites More sharing options...
scashell Posted July 17, 2007 Author Report Share Posted July 17, 2007 thanks . its the second one. really, they have configured 172.16.100.x/255.255.0.0 Its in the dhcp scope and dns that way. I know it's probably wrong, but that is how it is. thanks again. Quote Link to comment Share on other sites More sharing options...
rhwalker Posted July 18, 2007 Report Share Posted July 18, 2007 Quote: they have configured 172.16.100.x/255.255.0.0 and have also configured an overlapping inconsistent subnet of 172.16.102.x/24 ? If so, that is a problem. Broadcasts and routing won't work right. You might point your network people to Section 3 of RFC-1597: RFC-1597 The private address space 172.16.x.x is defined as a Class B network (/16). Russ Quote Link to comment Share on other sites More sharing options...
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