Ubuntu QA:
BlogBrainstormPackage status
Log in
Ubuntu QA
The Ubuntu community has contributed 21986 ideas, 135057 comments, 2615221 votes
Idea sandbox Idea sandbox
Popular ideas Popular ideas
Ideas in development Ideas in development
Implemented ideas Implemented ideas
Idea #25648: Ubuntu should warn if your IP is in conflict

bug This idea was marked as already implemented the 15 November 10.
Written by lotif the 20 Aug 10 at 19:51. Related project: Network Manager. Status: Already implemented
Rationale
Right now, if you manually set an IP in Ubuntu and if this IP is already registered in your network, or if somebody try to pick your IP by mistake or something, Ubuntu simply does nothing and let you without internet and without knowing what's going on. That's not right.

490
votes
closed
Solution #1: Ubuntu should warn that your IP is in conflict in the network
Written by lotif the 20 Aug 10 at 19:51.
A little warning and a red sign next to the connection indicator means a lot in usability.

A picture is worth a 1000 words.


63
votes
closed
Solution #2: Add help link/button to #1 solution with #3
Written by Oxwivi the 24 Aug 10 at 08:16.
A non-technical and standard user will not understand what to do in such a situation. A fix button bay help, but if it doesn't, a help link/button would go a long way to solve the problem.
160
votes
closed
Solution #3: Add Fix button to solution #1
Written by DaedalusPrime the 24 Aug 10 at 11:58.
Clicking the "FIX" button would attempt to change the IP address automatically by 1) if DHCP is enabled, renew the IP, or 2) if not DHCP, perform a search for an IP that appears to be open on the current subnet, using ipwatchd or a similar mechanism.
87
votes
closed
Solution #4: Make IPwatchD a default app
Written by lotif the 24 Aug 10 at 13:27.
As some pointed out, there's already an app out there which makes the job pretty well: IPwatchD. Let's make it a default app!



The only drawback I see is that the warnings aren't any further than this message. It should add an icon below the connection icon, like in Solution #1.

To install it, go to http://ipwatchd.sourceforge.net/ or just search for ipwatch on synaptic.
-44
votes
closed
Solution #5: Just fix it (and report it)
Written by ivanpd the 30 Aug 10 at 14:42.
I think part of the Ubuntu philosophy is that the user will be provided with a reasonable solution that works in most cases by default. Instead of complaining and allowing the user to fix it, I think the right approach would be:
- If DHCP is enabled, request a new IP with no user intervention.
- If DHCP is not enabled, allow the user to fix it automatically (as described in #3, no-dhcp) or to change the configuration by hand.

I don't have the time to draw anything (help is welcome to show this idea), but something similar to the pic in #1 with the text "Enable automatic fix or change settings by hand" would do.

Regarding the design, I think "Enable automatic fix" and "change settings by hand" could both have the appearance of web links (instead of buttons).
-51
votes
closed
Solution #6: Display "network misconfiguration" message + disable networking
Written by amay82 the 1 Sep 10 at 14:23.
If someone picks an IP address manually, (s)he should know what (s)he is doing, so a generalised "network misconfiguration" message + disabling the network should be enough. The rest can be seen in the system logs.

Propose your solution

Attachments
No attachments.


Duplicates


Comments
Akerbos wrote on the 21 Aug 10 at 21:08
I am not sure wether it is possible to find out wether there is a conflict. Maybe an active lookup before broadcasting the own address can do the job.

Define "subnet"! Does you machine have knowledge of how far to look for conflicts?

Akerbos wrote on the 22 Aug 10 at 08:44
Yes, it does, thanks to subnet mask.

Darwin Survivor (Brainstorm moderator) wrote on the 22 Aug 10 at 12:04
The problem with trying to detect another machine with the same IP (with say a ping) is that your machine would first need an IP for the other one to respond to. Unless there's something I'm missing here it sounds like a pretty big catch22.

If however there is a way to detect it, I *definitely* agree that a warning/error is called for.

loldrup wrote on the 23 Aug 10 at 06:10
The error message should also suggest ways the problem can be solved. For example by including a link that skips the static IP and tries to aquiere a IP via DHCP instead.

tntricker wrote on the 23 Aug 10 at 06:40
@Darwin - Pinging wouldn't do anything even if the other device didn't exist, the routers ARP would have to be analyzed.

Actually this has already been implemented in Linux

http://ipwatchd.sourceforge.net/ - please look for ipwatch in the Ubuntu repos.

lotif wrote on the 23 Aug 10 at 11:53
Darwin Survivor,

I don't know how it can be done, but AFAICT M$ already do this in windows...

lotif wrote on the 23 Aug 10 at 11:54
loldrup,

I thought about this, but didn't put on the mockup... maybe an idea #2?

lotif wrote on the 23 Aug 10 at 11:59
tntricker,

this is a great app...does exactly what I was thinking... integrate it with notify-osd and we're all set to make it a default app!

idea #3?

Darwin Survivor (Brainstorm moderator) wrote on the 23 Aug 10 at 12:18
#lotif I think you may be thinking of detecting duplicate "names". Conflicting IP's are much harder to deal with since 2 machines can talk perfectly fine with each other at the IP layer as long as they don't rely on names to determine the other machine's IP address.

lotif wrote on the 23 Aug 10 at 15:00
Darwin Survivor,

Well, I don't think so... If a package is addressed to an IP and this IP exists in two machines, to which one the router will deliver the package? At least in my empirical tests, when 2 machines have the same IP in the same subnet, one of them ends without an internet connection...

Anyway, tntricker showed us a pretty nice app that apparently does the job. I'll test it later and if it succeeds, i'll post as new solution to this idea...

Akerbos wrote on the 23 Aug 10 at 21:33
I guess it sends sometime do one, sometimes to the order, depending on which machine's MAC has been entered under this IP most recently.

Suggesting DHCP as solution is no good idea. In a fixed-IP network, it'd be wrong to do so.

tntricker wrote on the 23 Aug 10 at 23:13
When there's an IP conflict the router will throw an error, from then on it's behavior is undefined and is dependant on the router. Some routers will forward packets to both devices but it usually depends on which device sends an ARP response the fastest, or the one last stored in the routers ARP cache.

"How IP Address Conflicts Cause Problems"
http://www.tech-faq.com/ip-address-conflict.html


walterav wrote on the 25 Aug 10 at 10:26
Do you think a lot of unexperienced people do know what that message means and what to do?

The problem will only happen when people have a problem with their router. Experienced users who setup manual ip-address might not find this a real problem, but this pop-up may help them. Although it does look good and clean but windows also pops up allot of messages...

lotif wrote on the 25 Aug 10 at 11:53
I know unexperienced user will not know what this means. What I think is a wrong behavior is ubuntu tells nothing when something wrong is going wrong. If something is wrong somewhere, the OS should warn the user.

Matthias Müller-Reineke wrote on the 26 Aug 10 at 09:08
Unexperienced users should use DHCP and I expect that most of them do so. So such warnings will be read by more experienced users.

tntricker wrote on the 27 Aug 10 at 00:18
Errors that prevent access should always be reported in the least intrusive ways, (I.E. non-modal) but should still be reported.

Smart Viking wrote on the 7 Sep 10 at 21:27
Agreed, i resently set up an apache server and guess what? 3 other computers on the network had the same IP address, and i didn't even know it...

tikohajan wrote on the 18 Sep 10 at 09:29
I suggest the following solution, which is the middle of SOLUTION#1 and SOLUTION#3:

By pressing FIX button:

1) If IP address has been assigned by DHCP server, than the IP address should be REASSIGNED by DHCP.

2) If a static IP has been assigned to the host, the OS should warn ALL THE TIME, that there is an IP conflict.
(just right now an idea has been rised: it will be cool, if under the STATIC IP configuration fields, have a network administrator contact information bar, and this information will rise with the IP CONFLICT message. It because network admin sets the static IP configuration in the host OS, and will also fill the CONTACT field, for such kind of situation).

In both situation I suggest, that the FIX button also disable and enable again network adapter.

Thanks

James Haigh wrote on the 25 Oct 10 at 16:39
Solution #7: what about DHCP exhaustion or countermeasures? is a comment not a solution.

cheesehead (Brainstorm admin) wrote on the 15 Nov 10 at 13:06
The original Rationale (and Solution #1) is already implemented by the ipwatchd and ipwarchd-gnotify packages. Thanks to tntricker for pointing this out.

lotif wrote on the 8 Dec 10 at 17:14
If it is already implemented by a third party app but ubuntu does not have this app by default, I don't think this should be marked as implemented in ubuntu.

cheesehead (Brainstorm admin) wrote on the 10 Dec 10 at 13:25
The Rationale says nothing about including this feature by default. It only says the feature is lacking, and should be implemented.

I recommend a separate Idea for including those packages by default, since that's a different criteria. Be sure to do a bit of reasearch - the install CDs are already full and the Ubuntu Technical Board is constantly debating what can be removed or shrunk, so new packages should be small and provide a clear benefit to a large number of users.

There are several approaches to encourage after-initial-install use. For example, you can encourage use through a website with apt-url links.


Post your comment