I'm setting up DHCP on my new Sophos UTM installation and am looking for some advice before I end up making a mess of things! [LIST=1] Is it safe to assign static AND dynamic IP addresses from the same pool/DHCP definition? When assigning a static IP address I would like an entry to be added automatically to the DNS server. I've done some reading up on this but found it confusing; I think what I read may have applied to earlier versions which look like they may have done it differently. I've been setting up multiple DHCP definitions to allocate from a different range to different types of device (eg PCs vs mobile phones). Now that I've gone down this track I'm not convinced it's workable as the only way Sophos would know which pool to assign from is if it knows the device's MAC address - in which case I would need to have everything assigned statically. I've attached a screenshot to show where I'm setting up the static assignments - not sure if I'm doing it correctly in the right place so would love some advice. [/LIST] Thanks in advance for any help.

This discussion has been locked.

You can no longer post new replies to this discussion. If you have a question you can start a new discussion

DHCP and static mappings

I'm setting up DHCP on my new Sophos UTM installation and am looking for some advice before I end up making a mess of things!

[LIST=1]

Is it safe to assign static AND dynamic IP addresses from the same pool/DHCP definition?
When assigning a static IP address I would like an entry to be added automatically to the DNS server. I've done some reading up on this but found it confusing; I think what I read may have applied to earlier versions which look like they may have done it differently.
I've been setting up multiple DHCP definitions to allocate from a different range to different types of device (eg PCs vs mobile phones). Now that I've gone down this track I'm not convinced it's workable as the only way Sophos would know which pool to assign from is if it knows the device's MAC address - in which case I would need to have everything assigned statically. I've attached a screenshot to show where I'm setting up the static assignments - not sure if I'm doing it correctly in the right place so would love some advice.

[/LIST]

Thanks in advance for any help.

This thread was automatically locked due to age.

Parents

0 FrankBarmentlo over 10 years ago

can you also explain why it should be done outside the pool?

this will mean you have to manually configure those clients, since you cannot assign adresses server-side;
because when you do that, they have to be in the pool.
Cancel
Vote Up 0 Vote Down

Cancel
0 dilandau over 10 years ago in reply to FrankBarmentlo

can you also explain why it should be done outside the pool?

this will mean you have to manually configure those clients, since you cannot assign adresses server-side;
because when you do that, they have to be in the pool.

If you assign static IP addresses from within the dhcp pool their is a possibility of an IP conflict where more then one machine has the same IP (the static and the dhcp).

There are quite a few posts on this as it is a common question, here are a couple of threads:

http://www.astaro.org/gateway-products/management-networking-logging-reporting/43595-dhcp-reserved-ips-given-out.html
http://www.astaro.org/gateway-products/management-networking-logging-reporting/47859-dhcp-ip-conflict-new-image.html
Cancel
Vote Up 0 Vote Down

Cancel
0 philled over 10 years ago in reply to dilandau
If you assign static IP addresses from within the dhcp pool their is a possibility of an IP conflict where more then one machine has the same IP (the static and the dhcp).
There are quite a few posts on this as it is a common question, here are a couple of threads:
http://www.astaro.org/gateway-products/management-networking-logging-reporting/43595-dhcp-reserved-ips-given-out.html
http://www.astaro.org/gateway-products/management-networking-logging-reporting/47859-dhcp-ip-conflict-new-image.html

Sorry, but I'm a little confused about this after reading those threads. This is what I'd like to achieve:

Some IPs on my LAN need to be assigned to specific machines based on the MAC address of those machines.
Other devices on the LAN can be assigned any old IP address.

In order to achieve this, do I therefore set up TWO DHCP servers:
[LIST=1]
To serve the static IPs to devices with specified MAC addresses; should this have "Clients with static mappings only" ticked?
The other to serve any old IP address that's available?
[/LIST]
Cancel
Vote Up 0 Vote Down

Cancel

Reply

0 philled over 10 years ago in reply to dilandau
If you assign static IP addresses from within the dhcp pool their is a possibility of an IP conflict where more then one machine has the same IP (the static and the dhcp).
There are quite a few posts on this as it is a common question, here are a couple of threads:
http://www.astaro.org/gateway-products/management-networking-logging-reporting/43595-dhcp-reserved-ips-given-out.html
http://www.astaro.org/gateway-products/management-networking-logging-reporting/47859-dhcp-ip-conflict-new-image.html

Sorry, but I'm a little confused about this after reading those threads. This is what I'd like to achieve:

Some IPs on my LAN need to be assigned to specific machines based on the MAC address of those machines.
Other devices on the LAN can be assigned any old IP address.

In order to achieve this, do I therefore set up TWO DHCP servers:
[LIST=1]
To serve the static IPs to devices with specified MAC addresses; should this have "Clients with static mappings only" ticked?
The other to serve any old IP address that's available?
[/LIST]
Cancel
Vote Up 0 Vote Down

Cancel

Children

No Data