Just a thought: is there a way to make the CrosHost detection know the difference between testbed-ap and official jetstream profiles? I don't see anything obvious in /etc/lsb-release that would help, but I'm sure we could do *something* (like check for certain binaries in /usr/{s,}bin/).

That seems somewhat less fragile than modifying any test that might call create_host() on a testbed Whirlwind. (e.g., you'll need to modify server/site_linux_router.py too, no?)

It would be really great if we can stick to using the contents of lsb-release. 

Having cros_host probe for other files does not seem like a scalable approach, assuming more derivative host types could be added in the future.

From the the logs, I notice that the current AP image being used is based on R50-7849.0.0.

More recently, a CHROMEOS_RELEASE_BUILDER_PATH has been added to lsb-release (introduced in R54-8718.0.0). For the testbed-ap profile, the value of this field looks like:

  CHROMEOS_RELEASE_BUILDER_PATH=trybot-whirlwind-test-ap/R62-9784.0.0-b1

So if you can move to a build that is newer than 8718, maybe we could have is_jetstream return false if 'test-ap' is in the builder path?

I am working on a new test-ap build ( bug 702007 ). But the lab routers are all currently running 7849, so how to move them to the new build if network_WiFi_UpdateRouter is broken with 7849?

One other problem I can see with checking for 'test-ap' in CHROMEOS_RELEASE_BUILDER_PATH is that it wouldn't work for local builds by developers.

For existing routers, you could update their /etc/lsb-release boards to something like

  CHROMEOS_RELEASE_BOARD=whirlwind-ap-test

that would prevent them from being identified as JetstreamHosts.

For local developer builds using build_image, add the command-line option --builder_path=whirlwind-test-ap or similar to get the CHROMEOS_RELEASE_BUILDER_PATH set.

Proposal: modify network_WiFi_UpdateRouter to force CrosHost as a temporary fix to allow moving all lab routers to a new build (once  bug 702007  fixed). Then adjust is_jetstream as suggested to check for 'test-ap' in CHROMEOS_RELEASE_BUILDER_PATH.

sgtm

Seems OK. (I'm not a fan of getting developers to remember "--builder_path=whirlwind-test-ap", but it's better than nothing.)

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/autotest/+/1f7ae3a863dbbf417f3471ebcd7081162f8a42e7

commit 1f7ae3a863dbbf417f3471ebcd7081162f8a42e7
Author: Edward Hill <ecgh@chromium.org>
Date: Fri Aug 25 19:09:01 2017

Use CrosHost for testbed routers

Use CrosHost for all router hosts and avoid host detection.
Host detection would use JetstreamHost for Whirlwind routers.
JetstreamHost assumes ap-daemons are running.
Testbed routers run the testbed-ap profile with no ap-daemons.

TODO: crbug.com/757075 Fix testbed-ap JetstreamHost detection.

Also CHROMEOS_RELEASE_VERSION for trybot-whirlwind-test-ap/
R50-7849.0.0-b13 was wrong, causing the update to always be
performed.

BUG= chromium:748151 
TEST=network_WiFi_UpdateRouter
TEST=network_WiFi_VerifyRouter

Change-Id: I19f6fc8702493f038fa3563c459dee89db8bbbeb
Reviewed-on: https://chromium-review.googlesource.com/584823
Commit-Ready: Edward Hill <ecgh@chromium.org>
Tested-by: Edward Hill <ecgh@chromium.org>
Reviewed-by: Brian Norris <briannorris@chromium.org>

[modify] https://crrev.com/1f7ae3a863dbbf417f3471ebcd7081162f8a42e7/server/site_linux_router.py
[modify] https://crrev.com/1f7ae3a863dbbf417f3471ebcd7081162f8a42e7/server/site_tests/network_WiFi_UpdateRouter/network_WiFi_UpdateRouter.py