- For example, when Internet Access is strictly locked down. When multiple network interfaces are connected, passive polling may fail on one or more of these. If you believe you are affected by a Passive Polling issue please contact Microsoft support for assistance. Use the Cisco AnyConnect.
- The VPN is not prevented from running normally, nor is it being blocked from internet access (You can temporarily disable Tamper Protection in Norton settings to verify that it is not the cause of the trouble). I also use Cisco AnyConnect and have the same Tamper Protection entries, but no issues with VPN connectivity.
- Cisco AnyConnect clients connects to Internet via L3 device on inside zone of ASA (default gateway is on the remote network) 1. Cisco ASA MTU vs TCP MSS.
- When using Cisco Anyconnect VPN, the Windows Defender Security Center from Windows 10 V1803 opened cyclically a window to report the security status. He wrote: On several of our Windows 10 1803 Laptops, and when connecting to our VPN using Cisco Anyconnect, Windows Defender Security Centre’s – Security at a Glance constantly opens.
Introduction
VPN client software are: Internet Explorer, you will Client blocking Internet user's Cisco VPN connection on Cisco AnyConnect Secure Mobility Client Connection → I believe the latest VPN Uninstall and do if Internet disconnects VPN Fix SOLVED One gets the vpn client VPN Client and their to connect to my client - disconnects - reinstall.
This document describes the Cisco AnyConnect Mobility Client captive portal detection feature and the requirements for it to function correctly. Many wireless hotspots at hotels, restaurants, airports, and other public places use captive portals in order to block user access to the Internet. They redirect HTTP requests to their own websites that require users to enter their credentials or acknowledge terms and conditions of the hotspot host.
Cisco Anyconnect Disable Internet
Prerequisites
Requirements
Cisco recommends that you have knowledge of the Cisco AnyConnect Secure Mobility Client.
Components Used
The information in this document is based on these software versions:
- AnyConnect Version 3.1.04072
- Cisco Adaptive Security Appliance (ASA) Version 9.1.2
The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.
Background Information
Many facilities that offer Wi-Fi and wired access, such as airports, coffee shops, and hotels, require users to pay before they obtain access, agree to abide by an acceptable use policy, or both. These facilities use a technique called captive portal in order to prevent applications from connecting until users open a browser and accept the conditions for access.
Captive Portal Remediation Requirements
Support for both captive portal detection and remediation requires one of these licenses:
- AnyConnect Premium (Secure Sockets Layer (SSL) VPN Edition)
- Cisco AnyConnect Secure Mobility
You can use a Cisco AnyConnect Secure Mobility license in order to provide support for captive portal detection and remediation in combination with either an AnyConnect Essentials or an AnyConnect Premium license.
Note: Captive portal detection and remediation is supported on the Microsoft Windows and Macintosh OS X operating systems supported by the release of AnyConnect that is in use.
Captive Portal Hotspot Detection
AnyConnect displays the Unable to contact VPN server message on the GUI if it cannot connect, regardless of the cause. The VPN server specifies the secure gateway. If Always-on is enabled and a captive portal is not present, the client continues to attempt to connect to the VPN and updates the status message accordingly.
If the Always-on VPN is enabled, the connect failure policy is closed, captive portal remediation is disabled, and AnyConnect detects the presence of a captive portal, then the AnyConnect GUI displays this message once per connection and once per reconnect:
If AnyConnect detects the presence of a captive portal and the AnyConnect configuration differs from that previously described, the AnyConnect GUI displays this message once per connection and once per reconnect:
Blocking Internet Sites
Caution: Captive portal detection is enabled by default and is nonconfigurable. AnyConnect does not modify any browser configuration settings during captive portal detection.
Captive Portal Hotspot Remediation
Captive portal remediation is the process where you satisfy the requirements of a captive portal hotspot in order to obtain network access. Edge windows 8.
AnyConnect does not remediate the captive portal; it relies on the end user to perform the remediation.
In order to perform the captive portal remediation, the end user meets the requirements of the hotspot provider. These requirements might include payment of a fee to access the network, a signature on an acceptable use policy, both, or some other requirement that is defined by the provider.
Captive portal remediation must be explicitly allowed in an AnyConnect VPN Client profile if AnyConnect Always-on is enabled and the Connect failure policy is set to Closed. If Always-on is enabled and the Connect Failure policy is set to Open, you do not need to explicitly allow captive portal remediation in an AnyConnect VPN Client profile because the user is not restricted from network access.
False Captive Portal Detection
AnyConnect can falsely assume it is in a captive portal in these situations.
- If AnyConnect attempts to contact an ASA with a certificate that contains an incorrect server name (CN), then the AnyConnect client will think it is in a captive portal environment.
In order to prevent this issue, make sure that the ASA certificate is properly configured. The CN value in the certificate must match the name of the ASA server in the VPN client profile. - If there is another device on the network before the ASA that responds to the client's attempt to contact an ASA by blocking HTTPS access to the ASA, then the AnyConnect client will think it is in a captive portal environment. This situation can occur when a user is on an internal network and connects through a firewall in order to connect to the ASA.
If you must restrict access to the ASA from inside the corporation, configure your firewall such that HTTP and HTTPS traffic to the ASA's address does not return an HTTP status. HTTP/HTTPS access to the ASA should either be allowed or completely blocked (also known as black-holed) in order to ensure that HTTP/HTTPS requests sent to the ASA will not return an unexpected response.
AnyConnect Behavior
This section describes how the AnyConnect behaves.
- AnyConnect tries an HTTPS probe to the Fully Qualified Domain Name (FQDN) defined in the XML profile.
- If there is a certificate error (not trusted/wrong FQDN), then AnyConnect tries an HTTP probe to the FQDN defined in the XML profile. If there is any other response than an HTTP 302, then it considers itself to be behind a captive portal.
Captive Portal Incorrectly Detected with IKEV2
When you attempt an Internet Key Exchange Version 2 (IKEv2) connection to an ASA with SSL authentication disabled that runs the Adaptive Security Device Manager (ASDM) portal on port 443, the HTTPS probe performed for captive portal detection results in a redirect to the ASDM portal (/admin/public/index.html). Since this is not expected by the client, it looks like a captive portal redirect, and the connection attempt is prevented since it seems that captive portal remediation is required.
Workarounds
If you encounter this issue, here are some workarounds:
- Remove HTTP commands on that interface so that the ASA will not listen to HTTP connections on the interface.
- Remove the SSL trustpoint on the interface.
- Enable IKEV2 client-services.
- Enable WebVPN on the interface.
This issue is resolved by Cisco bug ID CSCud17825 in Version 3.1(3103).
Caution: The same problem exists for Cisco IOS® routers. If ip http server is enabled on Cisco IOS, which is required if the same box is used as the PKI Server, AnyConnect falsely detects captive portal. The workaround is to use ip http access-class in order to stop responses to AnyConnect HTTP requests, instead of requesting authentication.
Disable the Captive Portal Feature
Cisco Anyconnect Blocks Internet Windows 10
It is possible to disable the captive portal feature in AnyConnect client version 4.2.00096 and later (see Cisco bug ID CSCud97386). The administrator can determine if the option should be user configurable or disabled. This option is available under the Preferences (Part 1) section in the profile editor. The administrator can choose Disable Captive Portal Detection or User Controllable as shown in this profile editor snapshot:
If User controllable is checked, the checkbox appears on the Preferences tab of the AnyConnect Secure Mobility Client UI as shown here:
I'm going to update my original post above, but I was able to (finally) resolve the issue and wanted to share the solution. Thanks to some Internet searching, I learned of some settings in the Frontier/Netgear DSL modem/routers that is (as far as I can tell) designed to aid in forwarding various services through the router/firewall. From there, I was able to track it to the 'ALG' setting in the Port Forwarding area of the modem/router firmware. Here's what I did:
- Login to the DSL modem/router via the web interface
- Click on 'Advanced' at the top menu
- Click on 'ALG' under the section to the left denoted by the red toolbox icon
- Remove the checkmark for IPSec and click 'Apply'
- Reboot the modem/router
After doing this, I was able to successfully connect using the Cisco VPN Client software- hope this helps the next poor soul that runs into this! Hopefully it will save you that many hours over many days of troubleshooting it took me..
EDIT: Additional note- my home DSL router/model is a Netgear 7550 model, while it appears that both of the employees were issued the (presumably newer) Netgear D2200D model. The VPN seemed to pass through the 7550 model without an issue, so this may be an issue that's model specific.
Edited Oct 26, 2016 at 17:11 UTC