Re: integration of nonphysical interfaces in NM

[Tomislav Vujec <tvujec redhat com>]

> Colin Walters and I have talked about a configurable server that you
> could "ping" (like some internal server that you can't get to from
> outside) that would identify whether or not you're on the company LAN.
> Other than that, we could do something based on DHCP reply (ie if you're
> given an IP address in a specific range or the nameservers/DNS-search-
> name are somethign specific, then your on the internal network).

I guess that either this ping solution, or checking the domain-name option
in the DHCP offer would work. Address range checks might cause problems,
since it often happens that while visiting a client, I get the address on
their network which also exist in my corporate network, and that would
give false impressions. As alternative, we can use some of the application
servers DHCP options from the section 8 of the rfc 2132.

> Evolution should be getting online/offline support for NetworkManager at
> some future point, but the problem is that Evolution doesn't really have
> an "offline now" state.  What Evo does is to signal each plugin  that
> its /going/ offline soon, and when each plugin has repsonded OK, then it
> goes offline.  That's fine for syncing your mail, but if the cable is
> pulled you're /already/ offline, and you don't want Evolution to sit
> there and try to sync your mail when you're already offline.  This is a
> core assumption throughout evolution and its plugin structure, and isn't
> easily changed.  The second idea is to just make Evolution not check for
> new messages when NetworkManager says you're offline, but that's a hack
> and the only thing it solves is the annoying dialog that pops up when it
> tries to check the mail and can't contact the server.

That's precisely why I use OfflineIMAP and evolution with maildir folders.
However, two things should be implemented in the future:
1) Evolution should handle network disappearance gracefully, remembering
the non-synced stuff in some kind of journals.
2) NM should have a force offline feature, which would signal all
applications to go offline, and then somehow wait for them to do that like
the evolution does that for its plugins.

Now imagine the following scenario:
1) I close my laptop lid, signaling acpi to suspend
2) NM gets the suspend signal, and forces offline mode
3) All applications go offline
4) My laptop suspends
.....
5) I open the lid again, and the laptop wakes up
6) NM gets the signal and starts connecting through the available
preferred network to the Internet
7) NM announces Internet availability, and my yahoo account goes online in
the evolution
8) NM recognizes the current network connection as my home net, which has
a flag to start company VPN tunnel automatically
9) evolution switches my company email account to online

This is not a huge time server, but it is definitely something worth
implementing. Now days I almost need to use a checklist to make sure I
synced and unmounted everything before suspending.

Tomislav