Configure Ignite to use fixed ports

[to-bar]

The default Ignite configuration uses 3 ports for JMX:

1. com.sun.management.jmxremote.port - first available port from range 49112-65535

More details: https://github.com/apache/ignite/blob/2.7.6/modules/core/src/main/java/org/apache/ignite/internal/util/portscanner/GridJmxPortFinder.java

2. com.sun.management.jmxremote.rmi.port
3. port used by the Java Attach API

(2) and (3) are random, see: https://stackoverflow.com/questions/20884353/why-java-opens-3-ports-when-jmx-is-configured

Each time ignite is restarted, port 1) is increased by 1. The last used port is stored in /tmp/ignite.lastport.tmp and this file is not removed.

Example:

[root@ec2-15-236-133-49 ~]# ss -tulpnr | grep java
tcp    LISTEN     0      50       :::11211                :::*                   users:(("java",pid=7164,fd=83))
tcp    LISTEN     0      50       :::47500                :::*                   users:(("java",pid=7164,fd=95))
tcp    LISTEN     0      50       :::8080                 :::*                   users:(("java",pid=7164,fd=90))
tcp    LISTEN     0      50       :::10800                :::*                   users:(("java",pid=7164,fd=73))
tcp    LISTEN     0      50       :::49112                :::*                   users:(("java",pid=7164,fd=47))
tcp    LISTEN     0      50       :::47100                :::*                   users:(("java",pid=7164,fd=57))
tcp    LISTEN     0      50       :::38527                :::*                   users:(("java",pid=7164,fd=46))
tcp    LISTEN     0      50       :::44960                :::*                   users:(("java",pid=7164,fd=48))

[root@ec2-15-236-133-49 ~]# cat /tmp/ignite.lastport.tmp
49112

[root@ec2-15-236-133-49 ~]# systemctl restart ignite

[root@ec2-15-236-133-49 ~]# ss -tulpnr | grep java
tcp    LISTEN     0      50       :::11211                :::*                   users:(("java",pid=8390,fd=83))
tcp    LISTEN     0      50       :::47500                :::*                   users:(("java",pid=8390,fd=95))
tcp    LISTEN     0      50       :::8080                 :::*                   users:(("java",pid=8390,fd=90))
tcp    LISTEN     0      50       :::10800                :::*                   users:(("java",pid=8390,fd=73))
tcp    LISTEN     0      50       :::49113                :::*                   users:(("java",pid=8390,fd=47))
tcp    LISTEN     0      50       :::47100                :::*                   users:(("java",pid=8390,fd=57))
tcp    LISTEN     0      50       :::43938                :::*                   users:(("java",pid=8390,fd=48))
tcp    LISTEN     0      50       :::38085                :::*                   users:(("java",pid=8390,fd=46))

[root@ec2-15-236-133-49 ~]# cat /tmp/ignite.lastport.tmp
49113

We want to have fixed/static ports when possible for security reasons (firewall rules and DSAC scans).

References:
https://bugs.openjdk.java.net/browse/JDK-8234484
https://bugs.openjdk.java.net/browse/JDK-8035404
http://blog.markfeeney.com/2010/10/jmx-through-ssh-tunnel.html
https://stackoverflow.com/questions/15093376/jconsole-over-ssh-local-port-forwarding