Wireless can't ping wireless (more info)

[Jim Lewis]

>
>  I just realized that my wireless computers can't ping each other.
> Wireless to wired and vice versa is just fine. The IP addresses (DHCP)
> are all on the same subnet. If I switch to wired the computer can then
> ping a wired or wireless. The computers can all access the Internet at
> any time (either wired or wireless). I did some research and have
> determined the problem might be my router.
>
>   I use a LinkSys E3000 which I have had for a very long time. I checked
> their site and looked at the Release Notes for firmware upgrades. No
> mention of this issue and so I am hesitant to perform it (I did however
> download the latest file). I got into their Live Chat and the guy said
> since the unit is no longer in warranty I would have to pay to get
> assistance. I thought about doing this, but he could not guarantee
> success and the payment is not refundable. I thought that sucked and
> told him so.
>
>  So, does anyone have any ideas about how I might solve this? I am going
> to be rather surprised if the problem is not the router. If it matters
> here is my hardware:
>
> Fedora 14 - wired desktop
> Fedora 20 - wireless laptop
> Fedora 21 - wireless laptop (or wired)
> Fedora 21 - wireless laptop (or wired)
> Ubuntu 12.04.2 LTS - wireless (practically unusable because of Gnome 3)
>

  I just discovered something new: If I boot up one of my Fedora 21
laptops and try to ping it from any computer (wired or wireless), it
will fail with the same "Destination Host Unreachable" message. Note
that I am using the correct IP as shown by ifconfig. This laptop can
access the Internet just fine. Now here comes the good part: If I ping
my wired computer from this laptop it succeeds, and if I now try to ping
this laptop from the wired machine that now succeeds as well!  I have
tried this a bunch of times with the same result. Note that a wired
connection does not behave this way, I can ping it immediately. Also, I
just tried this with my Fedora 20 system (wireless) and it does NOT
fail, I can ping it immediately. So, assuming I haven't made some
brilliant error (I only make really stupid ones) there is something not
quite right in my Fedora 21 setups (yes, this is happening on both of
them).

 I am using the Mate Compiz spin. Once the connection is made and can ping
both ways it seems to stay that way without any further issues.

 I believe this also explains why wireless to wireless doesn't work. Since
it can't ping in either direction I can't "jog" it into working.

 One more data point: This also occurs if I disable the interface and
start it back up again. A reboot is not required to show the problem.



Jim Lewis