Error “Could not find a worker for worker name” configuring Apache 2.4 with mod_jk

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I am surprised there are so many different solutions for the same error online, but none worked for me. I wonder my issue is specific to Ubuntu.

I followed the below instructions, to try to front my Tomcat 9.0 with Apache 2.4.41 on Ubuntu 22, but I get the below error

jk_handler::mod_jk.c (2999): Could not find a worker for worker name=worker1

From the log file at /var/log/apache2/mod_jk.log (I believe this was the default). Any pointers greatly appreciated.

  1. Install mod-jk

    sudo apt install libapache2-mod-jk

  2. Setup workers.properties

Open if exists or create a file workers.properties in /etc/apache2 and paste the following:

# Define 1 real worker using ajp13
worker.list=worker1
# Set properties for worker (ajp13) - use of ip address apparently this solved some problems for some users
worker.worker1.type=ajp13
worker.worker1.host=127.0.0.1
worker.worker1.port=8009

  1. Edit jk.conf / httpd-jk.conf to tell Apache how to find my Tomcat, I have mine at /etc/apache2/mods-available/httpd-jk.conf (Or /etc/apache2/mods-available/jk.conf if jk.conf is present, according to some posts). In this file, change the JkWorkersFile property to(wherever you have yours):

    JkWorkersFile /etc/apache2/workers.properties

  2. Open /etc/apache2/sites-enabled/000-default.conf and:

  • Update ServerAdmin to whatever email you like to use

  • add the JkMount line in your VirtualHost configuration

    <VirtualHost *:80>
  JkMount /* worker1
</VirtualHost *:80>
  1. Tomcat 9.0 Server.xml changes
  • comment Connectors with 80, 8080 and 443, uncomment ajp/1.3 Connector with port 8009
  • add property secretRequired=”true” in ajp connector element, use ipaddress in element 127.0.0.1 [Another thing I learnt after a lot googling! I suspect this applies to newer versions of Tomcat only]
  1. Restart Tomcat and Apache2

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