Cisco Vpn Unable To Connect

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Cisco Vpn Unable To Connect

The Cisco VPN client has problems with some older (and sometimes newer) home routers, usually with specific firmware versions. If you have users with consistent connection problems, ask that they. Cisco VPN - Connection failed unsuccessful domain name resolution This article refers to the Cisco AnyConnect VPN. If you're looking for information on the Prisma Access VPN Beta that uses the GobalConnect app, see: istcontrib:Prisma Access VPN Beta Landing Page. The fix is quite simple actually, go to Network Connections from Control Panel, right-click Cisco AnyConnect Security Mobility Client Connection, and choose Properties. Then disable IPv6, change IPv4 IP settings from Fixed IP to Dynamic. Close all Network Properties dialog boxes, and try VPN connecting again. It should go through fine now.

VPN Tracker automatically runs the test for every new Internet connection it is able to detect but even if a connection has been tested before, there are various reasons why the behavior of that connection may have changed in the meantime. Reboot the computer. Whenever Cisco Anyconnect connects successfully to a network, it will automatically open a command prompt window in the background, silently pinging google.com to receive replies back, thus allowing Network & Sharing Center to detect internet access, and resolve the yellow exclamation.

This article refers to the Cisco AnyConnect VPN. If you're looking for information on the Prisma Access VPN Beta that uses the GobalConnect app, see: Prisma Access VPN Landing Page.
If you're not sure which service you're using, see: How do I know if I'm using the Cisco AnyConnect VPN or the Prisma Access VPN?

Problem

You are trying to connect to MIT's VPN on vpn.mit.edu, but get an error:

The VPN connection failed due to unsuccessful domain name resolution.

Solution

First, make sure that the problem only affects the Cisco VPN app. Test vpn.mit.edu with other tools such as a web browser, or 'ping' the hostname.

The cause is not fully known, but this is seen more frequently when people are using Google Public DNS (DNS servers 8.8.8.8 and 8.8.4.4)

  • Try using another DNS server, such as your ISP's DNS server
  • Try sending some pings to vpn.mit.edu before connecting; these can help cache the IP address in your DNS cache.
  • Wait a few minutes and try connecting again; the connection can work if you try again later.

Contents

Introduction

This document briefly describes the possible error messages that appear during the installation of AnyConnect VPN client on Apple MAC machines and their corresponding resolutions.

Prerequisites

Requirements

There are no specific requirements for this document.

Components Used

The information in this document is based on these software and hardware versions:

  • Cisco ASA Security Appliance that runs software version 8.x

  • Cisco IOS® Router that runs Cisco IOS Software Release 12.4(20)T

  • Cisco AnyConnect Client software version 2.x

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.

Conventions

Refer to Cisco Technical Tips Conventions for more information on document conventions.

Error Messages

This section shows a list of error messages along with the solutions.

Package Corrupt Error Message

When AnyConnect 2.3 is launched from an Apple MAC machine, the Anyconnect Package corrupt or unavailable error message appears and eventually, the connection attempt fails.

Solution

This can be a problem with the absence of the MAC-related AnyConnect package on the flash of the router. Upload the suitable AnyConnect package for MAC in order to resolve this issue. Upload the corresponding AnyConnect package, which depends upon the MAC architecture. For MACs on the Intel processor, you need the i386 macos image and for MACs that run the Power PC processor (PPC) you need the powerpc macos image. These are example packages for your reference:

  • anyconnect-macosx-i386-2.5.3055-k9.pkg

  • anyconnect-macosx-powerpc-2.5.3055-k9.pkg

Split DNS Issues

When split DNS is enabled on an AnyConnect setup, it is found that all the DNS queries are sent in clear but not tunneled. This is a problem with only the Apple MAC machines and works fine with Windows machines.

Solution

This behavior is observed and filed in Cisco bug ID CSCtf03894 (registered customers only) . In order to resolve this issue, you can upgrade to the AnyConnect release 3.0.4235, which has the Split DNS Functionality Enhancement. As a workaround, you can also use the built-in IPSec VPN client supported by Apple, which does not have this issue.

SVC Error Message

The launch of AnyConnect from a Macbook Pro running OSX Leopard is not successful. The VPN gateway is ASA running 8.0.4. The connection fails and the SVC Message: 16/ERROR: Initialization failure (mem allocfailed, etc.) error message appears.

Solution

This can be a problem with the way the MAC machine attempts to connect to the ASA. First verify if any IPv6 adaptors are enabled on the MAC machine and check if MAC tries to contact ASA over the IPv6 network. If so, it fails as the IPv6 is not supported with AnyConnect. In order to resolve this, disable the IPv6 related services on the MAC machine and try to connect with an IPv4 address.

Web-based Installation Error Message when AnyConnect is Launched on MAC

Unable

There are intermittent issues with you launch the AnyConnect version 2.5 on the MAC with OSX 10.5.6. The web-based installation was unsuccessful error message appears. At that time, you are unable to download and install AnyConnect, and the browser used is Firefox. If you reboot the MAC machine, this fixes the issue temporarily, but intermittently, the issue happens again.

Solution

Verify if your VPN gateways are connected in Load-balancer mode. If it is connected, then there could be some DNS cache-related issues that cause improper DNS redirects. In order to resolve this issue, always try to map the DNS URL to connect to one specific VPN gateway only.

MAC OSX 10.6.3 is Unable to get to Internet

When you use the AnyConnect on a MAC machine, you can access the Internal Corporate network but you are unable to browse to the Internet. It neither works by FQDN nor by IP address. There is a proxy server in use for Internet traffic.

Solution

The issue can be due to the length of the PMTU. Verify the existing MTU size on the VPN gateway, for example, ASA and modify it to a lesser value. In this sample output, the mtu size is reduced to 1204 from existing 1400.

AnyConnect on MAC fails to launch to Cisco IOS Router

Bit

The attempt to launch AnyConnect in standalone mode to a Cisco IOS® Router running Cisco IOS Software Release 12.4(20)T is unsuccessful. The anyconnect internal error (state: not connected) error message appears.

Solution

Cisco IOS Software Release 12.4(20)T supports AnyConnect on MAC in standalone mode without any problem. In order to resolve this, try to use the complete URL when you connect to the Cisco IOS head-end device. This is a sample URL:

If this issue persists, contact Cisco TAC (registered customers only) for further troubleshooting.

Note: You need to have valid Cisco user credentials to contact Cisco TAC.

Wireless CSSC for an Apple MAC

Currently, the NAM module on the AnyConnect 3.0 product replaces the Cisco Secure Services Client (CSSC). Refer to Network Access Manager (Replacement for CSSC) for more information. There is no current plan to enable NAM to support MAC OSX platform.

Unable to Upgrade Firefox while AnyConnect is Installed on MAC

This error message appears when you upgrade Firefox on Apple machine version 10.6:

On machines that use softtokens, this error message appears:

Cisco Vpn Cannot Connect To Remote Desktop

It is observed that these MAC machines have AnyConnect version 2.5 installed. The current version of Firefox is 3.6.13.

Solution

This behavior has been tested and filed in Cisco bug ID CSCtn93915 (registered customers only) . As a workaround, you can try any of these described options.

  • Uninstall AnyConnect, upgrade Firefox and then install AnyConnect again.

  • Uninstall the current version of firefox then install the new version. All other upgrades after this should work fine.

Web-based Installation of AnyConnect Hangs

The authentication phase works fine but the VPN system hangs at the Using Sun Java for installation phase.

Solution

The issue could be with the Java and Web applet settings on the machine. Sometimes, Java gets stuck when you use the web launch with MAC machine. Refer to Cisco bug ID CSCtq86368 (registered customers only) for more information. In order to resolve this issue, follow the below steps.

  1. Uninstall AnyConnect.

  2. Open Java preferences.

  3. Change to run applets in their own process.

  4. Drag the 32 bit Java on top.

    If this does not help, upgrade the AnyConnect client to the latest available release.

Unable to Launch AnyConnect on MAC

You are unable to launch AnyConnect on the MAC machine due to certain incompatible software. What are other options to use this MAC machine as a remote access VPN client?

Solution

Refer to What options do I have for providing remote access to Mac users? for more information. Refer to IPSec VPN client for Apple MAC for more information and complete details.

Unable to Download the MAC AnyConnect Package

There are issues when you download the AnyConnect for MAC software from Cisco.com.

Solution

Unable To Connect Remote Desktop When Cisco VPN Client Is ...

Open the Cisco AnyConnect VPN Client home page and click on Download Software (registered customers only) on the right hand side of the web page. Choose the required software package and download with valid Cisco user credentials.

VPN Client Unable To Connect - Cisco Community

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