Hi, a small, hopefully not too bikesheddy note from a user perspective: On Thu, Nov 07 2019 08:59:54 +0000, Stuart Henderson wrote: > On 2019/11/06 19:17, Stefan Sperling wrote: > > This diff allows the root user to trigger a background scan with: > > > > ifconfig iwm0 scan > > > > It supports two use cases which are currently not supported: > > > > 1) It will force an attempt at finding a better AP, even if the > > current AP is above the signal level threshold which will usually > > trigger a background scan. > > > > 2) It will update the list of cached APs. The updated list will be > > shown by subsequent invocations of 'ifconfig scan'. This allows the > > root user to view an up-to-date list of available networks without > > disassociating from the current AP. Currently, the list is updated only > > if a background scan is triggered via the signal strength threshold. > > > > Suggested by sthen@ > > > > ok? > > I'm finding this very helpful, if I'm on a low signal but working AP and > suspect that another one may be better this allows me to easily rescan > and (fairly seamlessly) move to a better one. Latency is a little higher > for a few seconds while the scan completes but packets continue flowing. > > Currently the only way to trigger a scan on a bgscan interface (unless > moving to a low signal area) is ifconfig down+up which interrupts > connectivity. > > The main thing I'm unsure about is whether to restrict this to root (as > this diff does) or not, there are arguments both ways - some will think > that it's also useful for an unprivileged user to be able to trigger a > search for a better AP, some will think that it's more useful to prevent > an unprivileged [possibly remote] user from being able to potentially > trigger a move to a different AP. Anyway this is an improvement and we > could remove the restriction later if wanted, so I'm OK with this as-is.
I think it might be a little confusing to make this operation implicit in another operation (ie. list APs), and for root only. How does a user find out about this feature? Wouldn't it be better to have a separate command to trigger the scan, eg. 'rescan'? That could be documented and restricted to root. -- Lauri Tirkkonen | lotheac @ IRCnet
