ip conflict on boot

At first I thought about putting this into Wish list, but I thought a more general discussion would be appropriate.
Yesterday I factory reset my router, at which point I had to reconfigure the PC to use various static IP addresses.
Once I’d finished and got everything up and working again I fired up my pandaboard.
On bootup it hung at SetupNet, it never seemed to complete.
Once I went through the steps in my head, the only thing left was an IP conflict. Which was correct the PC and the pandaboard now had the same static IP reserved.
It would be nice if there was some kind of timeout on the ipconfig process and make it interuptable and even better a message coming up saying “Idiot, you have a conflicting IP” rather than hanging forever (well patience isn’t my strong point, so maybe there is a timeout – but if there is it is far too long!)
Whilst I had no real issues debugging the problem and it only took about 5 minutes, it was frustrating and I’m not exactly a noob.
I had loads of thoughts go through my head, is it network layer (no the link came up correctly), is it the updated ROM (no it worked a couple of days ago), is it the updated !Boot (again it worked a couple of days ago), have files got corrupted.

Ideas and thoughts around the networking setup in RISC OS?
Do people find it easy or painful when things go wrong?
Is it easy to setup and configure?

I decided long ago that the easiest way to do things is to set up all the machines on my LAN with fixed IP addresses. I also allow a small pool of DHCP addresses on the router and each of the wifi access points so that anyone can connect (wired or wireless) and get an address that doesn’t conflict with the fixed addresses.

Since the addresses are fixed, they can go in the Hosts file of each machine, which allows every host to be pinged, connected to, etc. by name. The Hosts file can be copied between machines whenever it is updated.

I think it’s much easier than using DHCP.

I think it’s much easier than using DHCP.

It’s a view.
Personally speaking I think, and my work colleagues too, manually assigned addresses are a pain in the nether.

But then I use some machines at/from home and at work. At work I have 4500+ wired devices, 600+ wireless AP’s feeding numerous wireless devices and we long since binned the idea of doing things with hosts files.

Decent routers (and even the ones supplied by BT) allow a setting of “always use this address” which means the machines have a “fixed” address offered by DHCP.

Since DHCP and DNS are working nicely together all machines have the correct settings – always.
Since the addresses are “fixed” I can, if so inclined, add the details of all to the hosts files on the client machines – I prefer not to make the effort.

To answer Malcolm’s query:

Leave the client machines as DHCP, work on the router and set one configuration correctly – done.
Should you add another machine, leave it as DHCP and plug in. It works.
You want a fixed address on that machine, alter the router/DHCP server config to always hand out the same IP to that specific MAC. Done.

All comments apply equally to home or work, although at work the hosts file idea is insane.

at work the hosts file idea is insane.

Yes, but that isn’t a relevant context here.

One difficulty we still have with RISC OS, and you don’t have at work, is that host IP addresses should be automatically put into DNS, so you can connect and ping by name without needing a Hosts file.

I’d be interested to know the protocols involved.

I have my router set up to allocate DHCP addresses but to allocate a fixed Ip address to certain (specified) MAC addresses. That means that my printer has a predictable static IP address although as far as it is concerned it just uses DHCP.

That’s definitely the best way to do it if your router supports it. You can change the DNS server (for example) in the router and all clients get updated when they next renew their lease, rather than going to each one and editing the settings individually.

but to allocate a fixed Ip address to certain (specified) MAC addresses.

That’s exactly how my Livebox is set up. Easiest way.

One difficulty we still have with RISC OS, and you don’t have at work, is that host IP addresses should be automatically put into DNS, so you can connect and ping by name without needing a Hosts file.

The BT supplied router, at home, takes the host name information sent by the client and inserts it into its local DNS cache as hostname.home so RISCPC1 can be pinged as RISCPC1.home (but not RISCPC1 with no suffix)

A number of people actually have the feature working in their home router but because they don’t ping the FQDN they erroneously believe their router doesn’t have the facility.

Don’t get me wrong the network side of RO needs work and the Resolver module is high on the list for needing a good sort out. However, even the current implementation does a good enough to get by job for a home network provided the router is half decent and configured properly.

As Rick put it:

That’s exactly how my Livebox is set up. Easiest way.

I did used to have it set as dhcp, but I noticed it was quite slow at doing dhcp so I moved it to static.
I think I’ll move it back to dhcp though now (as you said using a reservation)
My main point was that if you screw it up, it’s not simple to diagnose and fix. (for me it was relatively simple, but I spend half my life using vi in /etc ;-) )
As there is no notice of an IP conflict, just a jam on SetupNet. Also booting with Shift means clickty clicking !Boot doesn’t work, so you have to find and hand edit the configuration file.

My main point was that if you screw it up, it’s not simple to diagnose and fix. (for me it was relatively simple, but I spend half my life using vi in /etc ;-) )

That is the main point in recommending people use DHCP and do the config in one single location with the advantage that users can ask for advice on things like adding a reservation out on the net if their router documentation doesn’t specifically list it.
Since it’s just default settings for DHCP on the client there is nothing to get wrong.

Also booting with Shift means clickty clicking !Boot doesn’t work, so you have to find and hand edit the configuration file.

Which is where a single stepping boot option would be handy, especially if it also logs every stage to a system log which makes describing the fault to someone else a lot easier.