[Discuss] Networking oddity

[Murray Strome]

On 2015-08-23 05:12 PM, Alan W. Irwin wrote:
> On 2015-08-23 22:18-0000 Deryk Barker (Honorary Colleague) wrote:
>
>> I think I must be losing my marbles....
>>
>> Just installed Mint 17.2 for the fourth time in a week - this is on 4 
>> separate machines.
>>
>> Now for the strangeness: the latest install is on my main server, 
>> which serves music, video and print services.
>>
>> Even with the firewall disabled I cannot connect to this machine - 
>> ssh, vnc, nfs - at all, I simply get connections refused.
>>
>> As I say the firewall is disabled (the whole network is behind a 
>> firewall anyway) and I have all the relevant software (openssh-server 
>> tightvncserver nfs-kernel-server) installed.
>>
>> I put this on my main desktop machine and my wife's desktop and my 
>> laptop and had no such problems. I can't even see anything in the log 
>> files.
>>
>> And now for the latest piece of strangeness: I CAN print from another 
>> machine...
>>
>> If anyone has any thought, please let's have them.
>
> Hi Deryk:
>
> Can you summarize the situation as you are getting good networking on
> 3 machines but the 4th is failing to network with all 4 machines
> having the same distribution and _identical_ networking setup?
>
> If, for example, your networking setup is not absolutely identical on
> the one bad machine because it is a server, then I would try 
> temporarily to
> make that networking configuration absolutely identical to the others
> to see if that matters.
>
> If there is an absolutely identical networking configuration, then
> could your networking chip/card on that bad machine just be (1)
> accidentally disconnected, (2) bad, or (3) just not properly supported
> any more by the Linux mint kernel?  Tracing all physical connections
> might find something in the first case, and in all cases, you might
> want to try swapping in a different networking card (say from one of
> the working machines if those still have network cards) to see if that
> matters.
>
> I hope this discussion of some obvious possibilities might help
> you to find out what the real issue is if only by process of
> elimination.
>
> Anyhow, it is an interesting problem you have described, and I hope
> you will be able to figure it out quickly.
>
> Alan
> __________________________
> Alan W. Irwin
>
I had a problem like this once not long ago -- it turned out to be 
faulty ethernet cable (it had been working for years, but suddenly 
became faulty for no obvious reason). I replaced and things worked fine 
again.
Murray