Re: [gentoo-user] soliciting a DHCP lease / carrier lost

[Mick]

On Monday 03 Apr 2017 20:21:28 thelma@×××××××××××.com wrote:
> The new box I installed in remote location has a problem obtaining IP
> address.  The box was working perfectly on my local LAN.
>
> In remote location I assigned static IP to it 10.10.0.5

Where and how?  At the router IP address table, against the PC's MAC address?  
At the PC itself using a static IP address and gateway in /etc/conf.d/net?


> Previously this IP was assigned to a Virtual Box but I no longer use it,
> so I assign this IP to a new box.
>
> The box was working for a day, but now when I boot the box I get
> - soliciting a DHCP lease
> - carrier lost

The "carrier lost" error indicates a link going down.  The lease renewal is 
likely to fail at least while the link is down.  The link failure may be due 
to an electrical hard fault, e.g. faulty Cat5e cable, RJ45 socket/plug; or due 
to high electromagnetic interference.  Check the router stats for carrier lost 
errors.  If the counters show the link is being dropped regularly you should 
try to eliminate each component in the circuit the cause of the fault.


> Could the old IP get stuck somewhere in DD-WRT router?
>
> ping 10.10.0.5 - gives me no response.

You may find arping a better instrument for investigating the use of IP 
addresses in your LAN.


> The Cat5 is about 15-20meter long, I test it with a cable tester, it is
> good (all the lights light up in correct order).
> Cable is plugged in into a new switch.

Long cables are more susceptible to electromagnetic interference - keep their 
runs separate from mains cables.


> I'll try to assign different address to it tomorrow and will try a new
> router on Friday.

The new router should eliminate the router as the cause of the problem.
-- 
Regards,
Mick