The first step in troubleshooting phase-1 (IKEv2 in my case) is to confirm that there are matching proposals on both sides. The proposals include acceptable combinations of cyphers, hashes, and other crypto information. This is easy if you control both ends of the ASA VPN tunnel.
Full Answer
Why can’t I connect the AnyConnect VPN client to the ASA?
When a user cannot connect the AnyConnect VPN Client to the ASA, the issue might be caused by an incompatibility between the AnyConnect client version and the ASA software image version. In this case, the user receives this error message: The installer was not able to start the Cisco VPN client, clientless access is not available.
How do I configure IPSec VPN on a Pix/ASA security appliance?
For a PIX/ASA Security Appliance 7.x LAN-to-LAN (L2L) IPsec VPN configuration, you must specify the <name> of the tunnel group as the Remote peer IP Address (remote tunnel end) in the tunnel-group <name> type ipsec-l2l command for the creation and management of the database of connection-specific records for IPsec.
How does the ASA handle the VPN payloads?
This payload is decrypted, and its contents are parsed as additional payloads. The ASA sends the VPN configuration settings in the 'complete' message to the client and allots an IP address to the client from the VPN pool.
What order should the PIX/ASA and the VPN client be in?
They must be in reverse order on the peer. Refer to PIX/ASA 7.x and Cisco VPN Client 4.x with Windows 2003 IAS RADIUS (Against Active Directory) Authentication Configuration Example for a sample configuration that shows how to set up the remote access VPN connection between a Cisco VPN Client and the PIX/ASA.
How do I troubleshoot Cisco VPN connection problems?
How do I fix the Cisco VPN issues on Windows 10?Repair the installation. In the Windows Search bar, type Control and open Control Panel. ... Allow VPN to freely communicate through Firewall. ... Use a more reliable VPN. ... Tweak the Registry. ... Perform a clean reinstallation.
How can I check my ASA VPN status?
Please try to use the following commands.show vpn-sessiondb l2l.show vpn-sessiondb ra-ikev1-ipsec.show vpn-sessiondb summary.show vpn-sessiondb license-summary.and try other forms of the connection with "show vpn-sessiondb ?"
Which command is used to check VPN tunnel is up or not?
This command “Show vpn-sessiondb anyconnect” command you can find both the username and the index number (established by the order of the client images) in the output of the “show vpn-sessiondb anyconnect” command.
How do you troubleshoot a crypto tunnel?
There is couple of things that you need to check.Check firewall policies and routing.Run packet tracker from Firewall and check vpn traffic flow.Check Firewall Inside local route to reach inside hosted network/servers.Make sure remote subnet should not overlap with your local Lan.More items...
How configure Cisco ASA site to site VPN?
1:0814:10Cisco ASA Site-to-Site VPN Configuration (Command Line)YouTubeStart of suggested clipEnd of suggested clipFirst of all we need to go into configuration mode so config T and now we're going to enable ISOMoreFirst of all we need to go into configuration mode so config T and now we're going to enable ISO camp on the outside interface that ISO camp is the handshake part of the configuration.
How do I configure IPsec on ASA firewall?
To configure the IPSec VPN tunnel on Cisco ASA 55xx:Configure IKE. Establish a policy for the supported ISAKMP encryption, authentication Diffie-Hellman, lifetime, and key parameters. ... Create the Access Control List (ACL) ... Configure IPSec. ... Configure the Port Filter. ... Configure Network Address Translation (NAT)
How do I test VPN tunnel?
Check the current status using the Amazon VPC consoleSign in to the Amazon VPC console.In the navigation pane, under Site-to-Site VPN Connections, choose Site-to-Site VPN Connections.Select your VPN connection.Choose the Tunnel Details view.Review the Status of your VPN tunnel.More items...•
How do I check VPN routes?
You can use a tool like Wireshark to "sniff" the traffic on your local network. Wireshark will allow you to see which traffic is going where based on the source and destination IP addresses. Set up Wireshark on an interface that is between the hosts you want to test.
How do I check my VPN?
It's easy to check if yours is giving you this basic level of protection — or if you have a VPN leak.First, identify your actual IP address. ... Turn on your VPN and connect to any server. ... Search “what is my IP” again in Google (or use an IP lookup site) and check the result against your VPN's virtual IP address.
How do I test IPsec VPN connection?
In the GUI, a ping may be sent with a specific source as follows:Navigate to Diagnostics > Ping.Fill in the settings as follows: Host. Enter an IP address which is on the remote router within the remote subnet listed for the tunnel phase 2 (e.g. 10.5. 0.1 ) IP Protocol. ... Click Ping.
How do I check my IPsec VPN status?
To view status information about active IPsec tunnels, use the show ipsec tunnel command. This command prints status output for all IPsec tunnels, and it also supports printing tunnel information individually by providing the tunnel ID.
How do I know if IPsec is working?
There are three tests you can use to determine whether your IPSec is working correctly:Test your IPSec tunnel.Enable auditing for logon events and object access.Check the IP security monitor.
How do I check my IPsec tunnel status?
To view status information about active IPsec tunnels, use the show ipsec tunnel command. This command prints status output for all IPsec tunnels, and it also supports printing tunnel information individually by providing the tunnel ID.
How check VPN tunnel Linux?
The following script will:Run the ISPConnectivity.sh script every 5 minutes. ... Check if the tun interface is down, and start the vpn script if it is.Check connectivity if the tun0 interface is up. ... Send all failure output to a file in my home directory.
How do I check the uptime on my Cisco router tunnel?
show vpn-sessiondb xxxx -- will tell you Login time/Duration. Hi, You can use the command sh vpn-sessiondb remote to show the duration time. Hope it helps.
How do I know if Windows is running VPN?
To check if your VPN is working, follow these 3 simple steps:Check your original IP address. Make sure that your VPN is turned off and head to our “What is my IP address?” page, which will show your actual IP.Turn on your VPN and connect to a server. ... Compare your virtual IP address against your actual IP.
What is an ASA response?
The ASA generates a response to the IKE_AUTH message and prepares to authenticate itself to the client.
Why does ASA use Auth?
The ASA sends the AUTH payload in order to request user credentials from the client. The ASA sends the AUTH method as 'RSA,' so it sends its own certificate to the client, so the client can authenticate the ASA server.
Why does the client omit the Auth payload from message 3?
The client omits the AUTH payload from message 3 in order to indicate a desire to use extensible authentication. When Extensible Authentication Protocol (EAP) authentication is specified or implied by the client profile and the profile does not contain the <IKEIdentity> element, the client sends an ID_GROUP type IDi payload with the fixed string *$AnyConnectClient$*. The client initiates a connection to the ASA on port 4500.
Is EAP authentication allowed?
Authentication is done with EAP. Only a single EAP authentication method is allowed within an EAP conversation. The ASA receives the IKE_AUTH message from the client.
What is Cisco ASA?
Cisco ASA comes with many show commands to check the health and status of the IPSec tunnels. For troubleshooting purposes, there is a rich set of debug commands to isolate the IPSec-related issues.
What does "PHASE 1 COMPLETED" mean in Cisco ASA?
After pushing down the attributes, Cisco ASA displays the "PHASE 1 COMPLETED" message indicating that the ISAKMP SA is successfully negotiated, as demonstrated in Example 16-58.
How to check IPSEC SA?
You can also check the status of the IPSec SA by using the show crypto ipsec sa command, as shown in Example 16-51. This command displays the negotiated proxy identities along with the actual number of packets encrypted and decrypted by the IPSec engine.
How to check if IPSEC tunnels are working?
If you want to see if the IPSec tunnels are working and passing traffic, you can start by looking at the status of Phase 1 SA. Type show crypto isakmp sa detail, as demonstrated in Example 16-50. If the ISAKMP negotiations are successful, you should see the state as AM_ACTIVE.
What happens if NAT-T is not negotiated?
If NAT-T is not negotiated or a NAT/PAT device is not detected, they display the Remote end is NOT behind a NAT device. This end is NOT behind a NAT device message, as shown in Example 16-55. Example 16-55. debug Output to Show NAT-T Discovery Process.
How does a client request mode-config?
The client requests mode-config attributes by sending a list of client-supported attributes, as shown in Example 16-57. Cisco ASA replies back with all of its supported attributes and the appropriate information.
What happens after NAT-T?
After NAT-T negotiations, Cisco ASA prompts the user to specify user credentials. Upon successful user authentication, the security appliance displays a message indicating that the user (ciscouser in this example) is authenticated, as shown in Example 16-56.
What is the problem with AnyConnect?
Problem: AnyConnect client is pre-populated with the hostname instead of the cluster Fully Qualified Domain Name (FQDN).
Why is my VPN pool enlarged?
The issue occurs because of the ASA local IP pool depletion. As the VPN pool resource is exhausted, the IP pool range must be enlarged.
Why is port 443 not blocked?
Note: Make sure that port 443 is not blocked so the AnyConnect client can connect to the ASA. When a user cannot connect the AnyConnect VPN Client to the ASA, the issue might be caused by an incompatibility between the AnyConnect client version and the ASA software image version.
How does certificate authentication work?
In order for certificate authentication to work, you must import the client certificate to your browser and change the connection profile in order to use certificate authentication. You also need to enable this command on your ASA in order to allow SSL client-certificates to be used on the outside interface:
What is the error message when you try to authenticate in WebPortal?
When you try to authenticate in WebPortal, this error message is received: "Unable to update the session management database".
Does AnyConnect VPN uninstall itself?
The AnyConnect VPN Client uninstalls itself once the connection terminates. The client logs show that keep installed is set to disabled.
Is AnyConnect Essentials a VPN?
This is the normal behavior of the ASA. AnyConnect Essentials is a separately licensed SSL VPN client. It is entirely configured on the ASA and provides the full AnyConnect capability, with these exceptions:
Introduction
- This document describes how to understand debugs on the Cisco Adaptive Security Appliance (ASA) when Internet Key Exchange Version 2 (IKEv2) is used with a Cisco AnyConnect Secure Mobility Client. This document also provides information on how to translate certain debug lines in an ASA configuration. This document does not describe how to pass traffic after a VPN tunne…
Prerequisites
- Requirements
Cisco recommends that you have knowledge of the packet exchange for IKEv2. For more information, refer to IKEv2 Packet Exchange and Protocol Level Debugging. - Components Used
The information in this document is based on these software and hardware versions: 1. Internet Key Exchange Version 2 (IKEv2) 2. Cisco Adaptive Security Appliance (ASA) Version 8.4 or later The information in this document was created from the devices in a specific lab environment. Al…
CORE Issue
- The Cisco Technical Assistance Center (TAC) often uses IKE and IPSec debug commands in order to understand where there is a problem with IPSec VPN tunnel establishment, but the commands can be cryptic.
Scenario
- ASA Configuration
This ASA configuration is strictly basic, with no use of external servers. - XML File
Note: The UserGroup name in the XML client profile must be the same as the name of the tunnel-group on the ASA. Otherwise, the error message 'Invalid Host Entry. Please re-enter' is seen on the AnyConnect client.
Debug Logs and Descriptions
- Note: Logs from the Diagnostics and Reporting Tool (DART) are generally very chatty, so certain DART logs have been omitted in this example due to insignificance.
Tunnel Verification
- AnyConnect
Sample output from the show vpn-sessiondb detail anyconnectcommand is: - ISAKMP
Sample output from the show crypto ikev2 sacommand is: Sample output from the show crypto ikev2 sa detailcommand is:
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