Re: Check if my IP address has changed ?

[Stephen Butler]

Thanks David,

I've taken the problem up with the distro forum, and hope to resolve it.

Stephen.

> Message: 1

> Date: Tue, 12 Feb 2013 10:51:57 -0700
> From: David Breakey <address@hidden>
> To: address@hidden
> Subject: Re: Check if my IP address has changed ?
> Message-ID: <address@hidden>
> Content-Type: text/plain; charset="iso-8859-1"
>
> Even if it's not possible to do this directly in Monit, you should be
> able to hook into the interface management scripts (I believe a post
> ifup hook should be able to check whether the IP address is what you
> expect, and take whatever corrective action is deemed suitable; how to
> do this is utterly dependent on your distro).
>
> However, why are you needing to do this? If you're using a static IP,
> then this shouldn't be an issue to begin with, unless there's something
> wrong with your system's interface management scripts--and if you're
> using DHCP, then assigning a "static" IP is the responsibility of the
> DHCP server, not the client.
>
> Enterprise-class routers support static leases, where the DHCP
> server compares the MAC address to a fixed list and, if found,
> assigns the IP address in the list, rather than the usual
> round-robin approach. Typically, these "fixed" addresses are outside
> the normal DHCP range. Very handy when you want the convenience of
> DHCP, with the utility of fixed addresses (I use DHCP almost
> exclusively at home, with a short lease time; if I need to change
> network infrastructure--DNS, NTP, etc--I just reconfigure the DHCP
> server and it will hand out the new information when the leases are
> renewed, while preserving fixed IP addresses).
>
> I *never* configure network-critical servers this way; they are
> /always/ statically configured, but I only have one /critical/
> server in each of the networks I am responsible for (small
> networks).
>
> If you're using a home or home-office router, then you're
> /generally/ out of luck (commercially, this is considered a
> "premium" feature), unless you replace the firmware with something
> like OpenWRT (as I've done). If you decide to do this, check
> carefully that OpenWRT is compatible with your router hardware first.
>
> Or, run a standalone DHCP server that supports it; /dnsmasq/ handles
> this quite nicely if I recall (same software that OpenWRT uses, I
> think).