Chrome Version: 56.0.2924.87 (Official Build) (64-bit)
Chrome OS Version: 9000.82.0 (Official Build) stable-channel edgar
Chrome OS Platform: Acer Chromebook 14 (CB3-431)
Network info: Shared network (WiFi available at the office)

Please specify Cr-* of the system to which this bug/feature applies (add
the label below).

Steps To Reproduce:
(1) Connect to a WiFi network
(2) Use the Cisco AnyConnect app to attempt to connect to a VPN with the headend on the same network (e.g., the VPN gateway IP is the same address as the WiFi network's gateway IP address)
(3) Once the connection is "established", attempt to access anything internal or external

Expected Result: Ability to connect to both internal and external servers (this works fine when I am at home on a different WiFi network with a different IP address)

Actual Result: No ability to connect to anything internal or external at all, because the VPN connection is extremely unstable

How frequently does this problem reproduce? Always

What is the impact to the user, and is there a workaround? If so, what is
it?

I am unable to use my Chromebook to access internal servers (e.g., pages on our office's intranet, connecting to Linux servers behind the firewall using Secure Shell, etc.) while I am at the office. The VPN connection works fine when I am at home, on my home WiFi with a different IP address. Other users with Macs and Windows laptops are able to successfully connect to the VPN and access internal servers.

Please provide any additional information below. Attach a screen shot or
log if possible.

I have an AnyConnect log, but did not attach it because there may be sensitive network information in it that is difficult to sanitize.

For graphics-related bugs, please copy/paste the contents of the about:gpu
page at the end of this report.