How to force the Collector to use IPv4 to listen for Syslog messages

Question:

One of my Syslog Sources is listening on a IPv6 address. I am unable to configure my endpoints to send messages to this address. How do I force it to use IPv4 instead?

Solution:

To force the JVM to default to IPV4, you can add an optional Java parameter to the Wrapper configuration file:

1. Open /Sumo Logic Collector/config/wrapper.conf ~ line 69, under # Java Additional Parameters.
2. Add the following line:
   wrapper.java.additional.3=-Djava.net.preferIPv4Stack=true
3. To restart the collector, use: ./collector restart.

 Alternatively you can turn off IPv6 completely using these steps:

1. sudo gedit /etc/sysctl.conf
2. Add the following lines to the end of the file:

# IPv6 disabled 

net.ipv6.conf.all.disable_ipv6 = 1 

net.ipv6.conf.default.disable_ipv6 = 1 

net.ipv6.conf.lo.disable_ipv6 = 1

3. Run this command to reload sysctl settings; it will apply the changes immediately: sysctl -p.