On 2019 Feb 03 (Sun) at 11:49:46 -0800 (-0800), Ryan McRonald wrote:
:> Synopsis: The channel remains the same (switching between 802.11 networks)
:> Category: Networking sys/net80211 sbin/ifconfig
:> Environment:
: System : OpenBSD 6.4
:
:> Description:
:
:When switching between 802.11 networks the channel (if set) remains the same.
Tested on iwn*, but not other drivers
:
:> How-To-Repeat:
:
:Consider an /etc/hostname.if
: join Net1 chan 1
: join Net2 chan 2
:
:When the switch occurs from Net2 to Net1, the nwid is set to Net1 but the
channel remains set to 2. Therefore the system cannot connect to Net1.
:
:> Fix:
:
:I imagine best practice is to not to set a channel if using join in
/etc/hostname.if. However, I have a use case where I wanted to join a
particular AP by its channel.
:
:If you want to address this, one idea is that in ieee80211_node.c's function
ieee80211_set_ess() could set the channel to the channel obtained and scored in
the ieee80211_???_scan(). Or, it could set the channel to IEEE80211_CHAN_ANY.
Or perhaps it could call some of the clever channel logic already in the code
to determine what the channel ought be set considering band, mode, etc.
:
:For consideration, perhaps there are other settings (e.g. -autoconf ) which
could be set in /etc/hostname.if which maybe should be auto-unset in
ieee80211_set_ess()?
:
:Another consideration, by design ifconfig(8) retains settings unless
explicitly unset, for example:
:
: ifconfig if0 nwid Net1 chan 1
: ifconfig if0 nwid Net2
:
:At the second command the channel will remain chan 1. Perhaps unsetting the
channel when the nwid changes would be desired. Or are there good reasons for
'-chan' to be explicit and required?
:
:
Forcing a specific channel is working around a bug.
Join does not save any channel information, and any channel that is set
will stay sticky. Currently there is no intention to add that to join.
Please file a different bug describing your environment, and why the
auto-selected channel is incorrect. You may also want to include
information generated by "ifconfig iwn0 debug".
--
My mother loved children -- she would
have given anything if I had been one.
-- Groucho Marx
