Switching subnet /24 to /23
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Currently our DHCP server reside on an older DC. With all these configurations I want to move it to our new DC (failover cluster) at the same time. Can I skip step #8 and start #9 onward on the new DC?
Or at that point start fresh DHCP is better?
Same question for DNS as well. -
@LAH3385 said:
Currently our DHCP server reside on an older DC. With all these configurations I want to move it to our new DC (failover cluster) at the same time. Can I skip step #8 and start #9 onward on the new DC?
Or at that point start fresh DHCP is better?Moving to a new DHCP makes it easier. Just export, makes changes, move the file to the new DHCP server.
Then prior to import, unauthorized and stop the DHCP service on the original.
On the new server, just port and authorize.
Restart service and you should be good to go. -
@LAH3385 said:
Same question for DNS as well.
There is no moving DNS. If you made the new DC a DC properly, then it already has all of the DNS.
Now, if you are going to make this new DNS server the primary, then you do need to update that in the DHCP scope as well as in any static assigned devices.
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@JaredBusch said:
@LAH3385 said:
Same question for DNS as well.
There is no moving DNS. If you made the new DC a DC properly, then it already has all of the DNS.
Now, if you are going to make this new DNS server the primary, then you do need to update that in the DHCP scope as well as in any static assigned devices.
The reason I mentioned DNS is because I don't know what has been done to its configuration. DNS is probably the only section I rarely visit daily.
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@LAH3385 said:
@JaredBusch said:
@LAH3385 said:
Same question for DNS as well.
There is no moving DNS. If you made the new DC a DC properly, then it already has all of the DNS.
Now, if you are going to make this new DNS server the primary, then you do need to update that in the DHCP scope as well as in any static assigned devices.
The reason I mentioned DNS is because I don't know what has been done to its configuration. DNS is probably the only section I rarely visit daily.
Well, pull itup and go look at it. you will see everything is there. That is simply a function of making a Windows DC.
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When will you need IPV6?
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As a business or home user you will likely never need IPv6.
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IPv6 is for the world, as there are hundreds of billions of available IP addresses.
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@JaredBusch said:
This is easy, you just have to plan it out. Note, you cannot "change" the scope of your DHCP server. You can choose to add another or wipe it and reimport it via PowerShell (what I typically do).
- Understand what your new range will be. Since you are on X.X.1.X/24. the new scope will be X.X.0.X/23.
- Update your router LAN IP to use the /23. If it was X.X.1.1/24, it is now X.X.1.1/23.
- Update your DC (asusming a WIndows network here) to use the new /23.
- Put a test device manually on X.X.0.X/23 and make sure you have internet and can ping the DC.
- Update all of your static devices to the /23.
- Export the DHCP Scope via PowerShell
Export-DhcpServer -ComputerName dhcpserver.contoso.com -File C:\exportdir\dhcpexport.xml - Edit the XML file to expand the scope. Here is an example of one I did this on a couple years ago. Basically change the ScopeID, SubnetMask, StartRange, and add an ExclusionRange for the entire X.X.0.1-X.X.0.255 initially. You can delete this exclusion in the GUI later when you are ready to use it.
- Delete your current DHCP scope from the GUI.
- Import the updated scope from PowerShell.
Import-DhcpServer -ComputerName dhcpserver.contoso.com -File C:\exports\dhcpexport.xml. - Refresh the GUI, enable the scope, restart the service, etc.
- Make sure all the settings migrated in correctly.
- Force a machine to DHCP renew and you are done.
Does this looks about right? 1.1-1.30 belong to current static IP addresses
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@LAH3385 You noted the subnetmask as a /22 but noted the end range as 1.254. The end range of a /22 is 3.254.
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Am I reading that right that you want to to exclude the entire 192.168.0.1/24 subnet?
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@coliver said:
Am I reading that right that you want to to exclude the entire 192.168.0.1/24 subnet?
For the time being. yes. It will be open to public later. I don't have a solid game plan yet so might as well keep everything the way it is (starting at .1.xx)
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@LAH3385 said:
@coliver said:
Am I reading that right that you want to to exclude the entire 192.168.0.1/24 subnet?
For the time being. yes. It will be open to public later. I don't have a solid game plan yet so might as well keep everything the way it is (starting at .1.xx)
Ah, ok I was just checking.
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@coliver said:
@LAH3385 said:
@coliver said:
Am I reading that right that you want to to exclude the entire 192.168.0.1/24 subnet?
For the time being. yes. It will be open to public later. I don't have a solid game plan yet so might as well keep everything the way it is (starting at .1.xx)
Ah, ok I was just checking.
It is what I told him to do for the immediate change over. I suggested it, because every time I open up a range, I find something that was missed and suddenly people cannot do whatever task they need to.
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@JaredBusch
To make it simpler for me. Would /22 starting at 192.168.1.1 to 192.168.4.254 better than 192.168.0.1 to 192.168.3.254? -
@LAH3385 said:
@JaredBusch
To make it simpler for me. Would /22 starting at 192.168.1.1 to 192.168.4.254 better than 192.168.0.1 to 192.168.3.254?The /22 network that include 192.168.4.1 is 192.168.4.0-192.168.7.254.
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@LAH3385 said:
@JaredBusch
To make it simpler for me. Would /22 starting at 192.168.1.1 to 192.168.4.254 better than 192.168.0.1 to 192.168.3.254?it doesn't work that way. You don't get to pick which addresses are part of your /22, the layout of bits in the subnet mask do.
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Here is a page that talks about how subnetting works, and why it works how it does.
https://www.techopedia.com/6/28587/internet/8-steps-to-understanding-ip-subnetting/3 -
I see.. Gotta play by their rules.
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@LAH3385 said:
I see.. Gotta play by their rules.
Look at the screenshot provided above, it shows you the range.
