Network setup 'DHCP with manual address' changes to 'Using DHCP'

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Network setup 'DHCP with manual address' changes to 'Using DHCP'

I have setup my local network with a manual address and have observed that the setting changes without my doing to simply Using DHCP. I can't get the setup to continue using a manually assigned ip address. Even though I've saved the network settings preferences, they revert to 'Using DHCP'. Any ideas? Thanks in advance.

MacPro 3.0, Mac OS X (10.5.6)

Posted on Apr 2, 2009 12:16 AM

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Answer 1

Camelot

Level 9

58,311 points

Apr 2, 2009 9:01 AM in response to jbpatters

Are you sure that 'DHCP with Manual Address' is what you really want? It's not a common setup at all.

Most people either use DHCP or Manual, not the hybrid approach.

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Answer 2

jbpatters Author

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Apr 3, 2009 9:20 AM in response to jbpatters

Thanks Camelot,

Yes that what I want but if I know it doesn't work that way then I'll set up everything manually. I just find it peculiar that although I've specified a manual IP address and saved it, it still gets changed involuntarily. Perhaps you're right and I interpret the 'DHCP with manual address' incorrectly, but I don't think so.

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Answer 3

cwog

Level 1

98 points

Apr 6, 2009 5:02 AM in response to jbpatters

In the set up for my router (Vigor 2500V) I have the option of starting the DHCP at a number of my choice - this then allows me to manually allocate IP addresses to devices below the DHCP allocated pool range - I have a network printer in the fixed ip range as well as my prime tower machine, other machines get allocated IP addresses by DHCP

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Answer 4

Apr 6, 2009 6:26 AM in response to jbpatters

'DHCP with manual address' only works with DHCP servers that support the DHCPINFORM message.

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Answer 5

j.v.

Level 5

4,155 points

Apr 6, 2009 9:16 AM in response to jbpatters

If you "have setup (your) local network with a manual address," does that mean you have disabled DHCP in your router? If so, then you'd want to configure "manually" in your Sys Prefs > Network.

Or did you mean that you have setup a computer on your local network with a manual address using DHCP? (And that your router has DHCP enabled?)

If the router's DHCP is enabled, many routers will allow you to set aside a subset of IP addresses to the DHCP pool, and the remainder are, by definition, reserved for static addressing. Are you assigning the computer requiring a static IPA (but using DHCP defined gateway and subnet) an address falling within the static address range of your local subnet?

If you can't partition the address space between static IP addresses and DHCP-assigned IP addresses when DHCP is enabled, are you assigning a high-numbered IP address to the computer whose Sys Prefs has DHCP with manual address?

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Answer 6

jbpatters Author

Level 1

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Apr 6, 2009 9:23 AM in response to tele_player

Thanks tele_player, you might have something, I'll check if the DHCP server supports the DHCPINFORM message. I'm guessing it does but I want to make sure.

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Answer 7

jbpatters Author

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Apr 6, 2009 9:31 AM in response to j.v.

Thanks j.v. I've configured the router to allocate an address range and set aside a 'static' addresses for certain users on my local network. In the meantime I've configured the network on the machine that I'm having a problem with to a manual configuration. I also want to check tele_player's information about the DHCPINFORM message.

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Answer 8

Apr 6, 2009 10:35 PM in response to jbpatters

A few years old, but relevant:
http://support.apple.com/kb/TA21403?viewlocale=en_US

Also see RFC2131.

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Answer 9

jbpatters Author

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Apr 17, 2009 11:46 PM in response to jbpatters

Thanks to everyone that responded. The workaround to the problem appears to be a manual configuration; at least I haven't experienced the issue since changing the setup.

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