Network IP Address change notification

Zedcars said:

Hi,

I bought a Mac Mini just for the power, quiet fans and low wattage. I'm completely new to servers so please forgive me if this is obvious:

I keep getting emails from the System Administrator (I thought that was me!) informing me that:



Only the last digit changes.

Is this normal or something I should worry about? If it's normal, how do I stop all the emails? And if it is a problem, how do I solve it?

I actually don't really need all the server features, so was wondering if it would be better just to disable them somehow?

Thank you,
Darren

Click to expand...

If you are running this at home you are probably getting new IP's via DHCP. You will need a static IP to stop this.

Zedcars said:

Thanks for the reply.

Is there any reason why DHCP would be more advantageous than a static IP? To make it static, presumably I would have to set 'Configure IPv4' to 'Manually'?

Click to expand...

DHCP hands out available IP's as available. Servers should always use a static IP because when the IP changes it could disabled services or change paths that services rely on.

Mattie Num Nums said:

DHCP hands out available IP's as available. Servers should always use a static IP because when the IP changes it could disabled services or change paths that services rely on.

Click to expand...

Or Configure a DHCP reservation for the server.

It's odd that the IP address is changing if the mini isn't being rebooted as half way through the DHCP lease period the mini should send a request to the DHCP server to re-use its current IP address.

Is this a home server?

Are you using an Airport Extreme as your router? For some reason those totally ignore DHCP lease times. I have cameras that will just reboot (3 seconds of down time) and when they come back up the Airport Ext will give them a different address then what they had earlier that day. I set the lease time to 30 days and a reboot still resulted in a new address.

Picking up a new address often on a server can lead to problems especially if your accessing it via port forwarding. You definitely want to make a reservation if your router is an Apple device.

I know this is an old thread, but I am getting these emails all the time. I know why the ip address is changing, my question is how do I stop the freakin emails!

Just delete them.

Since I do not run the server OS, I don't know how to stop OS X from sending you emails, but you could configure your mail service/client to just delete them based a rule. I would suggest a combination sender/subject line rule.

Personally my recommendation is to use static IP assignments via DHCP.

How this is set up varies depending on the DHCP server (which I'm guessing is your router) but look for something like 'Static IP' or 'IP Reservations' or something like that in your DCHP config.

The reason I recommend this is because setting IPs manually on the devices a) has a greater margin of error and b) if you need to make a change you need to go back to that device - a pain if you have a number of devices to change.

With static assignments via DHCP there is less likelihood of cockup in the settings - since everything bar the device IP is a global setting so if it works for one it works for all. All IPs are set in one place so if you need to change a bunch you do it in just one place, update your config and you're done. Additionally as most kit is shipped enabled for DHCP it's one less setup step on a device to do.

Generally to set it up all you need is the MAC address of the network interface and the IP address you want to give to it - simple.

One thing to be aware of though, some DHCP servers insist that static assigned IPs must be within the IP range set up on the DHCP server. Others insist that its outside of that range* so check the documentation on your DHCP server beforehand to set it up correctly.

By which I mean the 'pool' of IPs available to the DHCP server - for the sake of argument lets say the DHCP server has 192.168.1.100-192.168.1.199 configured as its range (ie 100 devices). Best practice would be to keep the static IPs out of that (for example do static assignments on 192.168.1.10-192.168.1.99), but some routers wont be able to handle that.