How To Fix TG891 - Exception & raised; no application servers found

TG891 - Overview

• Message type: E = Error

• Message class: TG - Messages for Upgrade Repository Switch

• Message number: 891

• Message text: Exception & raised; no application servers found

What causes this issue?

The message server cannot be reached or does not give a list of
application servers available. The most common reason for this exception
is the missing message server. In the working directory of the SAP
system, you can find the trace file "dev_ms".

System Response

The upgrade stops with an error message.

How to fix this error?

Start the message server again, by restarting the SAP system, for
example. Using the test environment of the function module
TH_SERVER_LIST, check that the message server is running correctly.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message TG891 - Exception & raised; no application servers found ?

  The SAP error message TG891 indicates that there is an exception raised due to the system not being able to find any application servers. This can occur in various scenarios, such as when trying to log into the SAP system or when executing a transaction that requires application server access.
  Causes:
  
  Network Issues: There may be network connectivity problems preventing the client from reaching the application servers.
  Application Server Down: The application servers may be down or not running.
  
  Configuration Issues: The SAP system configuration may be incorrect, leading to the inability to locate application servers.
  Load Balancer Issues: If a load balancer is used, it may not be routing requests correctly to the available application servers.
  SAP Instance Not Registered: The SAP instance may not be registered properly in the SAP message server.
  Firewall Restrictions: Firewalls may be blocking access to the application servers.
  
  Solutions:
  
  Check Network Connectivity: Ensure that the network connection between the client and the