How to Tackle SQL Server Database Mirroring Error 1418 ?

Stacy Brown | February 4th, 2019 | High Availability |


SQL Server comes with several inbuilt features for proper maintenance or availability of the database that supports failover clustering. One of them is SQL Server Database Mirroring, which is a disaster recovery and high availability technique that works only with databases using full recovery model. Though mirroring helps in increasing availability and data protection, the users encounters a common error while using Mirroring feature, known as SQL Server Database Mirroring Error 1418. The blog discusses about what is Microsoft SQL Server error 1418 Mirroring and how to resolve it.

SQL Server Database Mirroring Error 1418

The SQL Server Database Mirroring is a feature that involves two SQL Server instances where a copy of a single database is created on the same or different machines. One SQL Server instance that acts as a primary instance is called principal and other one is a mirrored instance called the mirror. One of the common Microsoft SQL Server error 1418 associated with mirroring that displays the following error message:

“The server network address cannot be reached or does not exist. Check the network address name and that the ports for the local and remote endpoints are operational.”

This error happens when the server network endpoint did not respond because the specified server network cannot be reached or it does not exist.

How to Troubleshoot Microsoft SQL Server Error 1418?

SQL Server Database Mirroring Error 1418 occurs due to connection problem between endpoints, the first thing we need to do is to check TCP/IP for the instance if it has been enabled or not.

Steps that need to be followed are:

  • Check if the system Firewall has not block SQL Server port.
  • Go to Computer Management → Service and Application → SQL Server 2005 Configuration → Network Configuration.
  • See if the TCP/IP protocol is enabled or not in Network Configuration and make sure that SQL SERVER port is by Default 1433.
  • Now check if TCP/IP protocol is enabled or not in Client Configuration Tab under Computer Management → Service and Application → SQL Server 2005 Configuration.

If the error cannot be resolved still, follow the below steps:

  1. Service Accounts Verification
    • CONNECT permissions to partner’s endpoints is required by SQL Server Service account
    • It is recommended that we use domain accounts for all partners.
    • For Local service, certificate authentication should be used.
    • For Network service, computer account should be used.
    • See the SQL log for errors.
  2. Ports Verification
    While configuring network for a database mirroring session, database-mirroring endpoint of each server instance should be used only by database mirroring process. If another process is listening on the port assigned to database mirroring endpoint, the database mirroring processes of the other server instances cannot connect to the endpoint.

    • Use the netstat command to display all the ports on which Windows-based server is listening.
    • Use Telnet to test if the port is open and something is listening.
    • Ensure no other SQL instances are connected on the server.
    • Check if Firewall is allowing traffic both directions & not blocking the port
  3. Ensure all instances can access every other partner
    • Ping each partner from one another.
    • To trace the path of the IP, use tracert to each partner
    • Double check the ports if ping or tracert fails
  4. Verify Endpoints
    • Ensure that all endpoints are started.
    • Make sure all endpoints are using same encryption algorithm.
    • Ensure that OS supports chosen encryption algorithm on all partners.


The blog has been aimed to study about the common error encountered by SQL database users while performing mirroring operation, also known as Microsoft SQL Server Error 1418. This error restricts server network endpoint from responding as the specified server network cannot be reached or it does not exist. It further suggests solution for users to overcome SQL Server Database Mirroring Error 1418 using the steps defined in the blog.