[Metalab Issues] #146: Intra-WiFI Connections Sometimes Don't Work

[Metalab Issues]

#146: Intra-WiFI Connections Sometimes Don't Work
-------------------+------------------
Reporter:  anlumo  |       Owner:
    Type:  defect  |      Status:  new
Priority:  major   |  Resolution:
Keywords:          |
-------------------+------------------
Description changed by anlumo:

Old description:

> I can't reach my iPad from my MacBook Pro, both connected to the metalab
> WiFi. The problem is that my Mac's arp requests do not get answered:
>
> {{{
> 00:06:52.576630 ARP, Request who-has 10.20.30.211 tell 10.20.30.189,
> length 28
> 00:06:53.577250 ARP, Request who-has 10.20.30.211 tell 10.20.30.189,
> length 28
> 00:06:54.578318 ARP, Request who-has 10.20.30.211 tell 10.20.30.189,
> length 28
> 00:06:55.578642 ARP, Request who-has 10.20.30.211 tell 10.20.30.189,
> length 28
> 00:06:56.579088 ARP, Request who-has 10.20.30.211 tell 10.20.30.189,
> length 28
> }}}
>
> When I connect from my iPad to my MacBook Pro using the browser, the
> connection is refused (because I don't have a web server open), but this
> action causes the iPad to show up on my Mac's arp table:
>
> {{{
> ? (10.20.30.211) at 1c:ab:a7:d5:b4:5d on en0 ifscope [ethernet]
> }}}
>
> Then I can connect in the opposite direction until the entry vanishes
> from the arp table (by timeout or upon deleting it manually) again.

New description:

 I can't reach my iPad from my MacBook Pro, both connected to the metalab
 WiFi. The problem is that my Mac's arp requests do not get answered:

 {{{
 00:06:52.576630 ARP, Request who-has 10.20.30.211 tell 10.20.30.189,
 length 28
 00:06:53.577250 ARP, Request who-has 10.20.30.211 tell 10.20.30.189,
 length 28
 00:06:54.578318 ARP, Request who-has 10.20.30.211 tell 10.20.30.189,
 length 28
 00:06:55.578642 ARP, Request who-has 10.20.30.211 tell 10.20.30.189,
 length 28
 00:06:56.579088 ARP, Request who-has 10.20.30.211 tell 10.20.30.189,
 length 28
 }}}

 When I connect from my iPad to my MacBook Pro using the browser, the
 connection is refused (because I don't have a web server open), but this
 action causes the iPad to show up on my Mac's arp table:

 {{{
 ? (10.20.30.211) at 1c:ab:a7:d5:b4:5d on en0 ifscope [ethernet]
 }}}

 Then I can connect in the opposite direction until the entry vanishes from
 the arp table (by timeout or upon deleting it manually) again.

 This behavior has been observed on other device combinations as well, and
 might be the cause why direct file transfers often fail here.

--

-- 
Ticket URL: <https://metalab.at/issues/ticket/146#comment:1>
Metalab Issues <https://metalab.at/issues>
Metalab is a Hackerspace in Vienna's first district.