Each machine that will run VMware Tanzu GemFire must meet the following requirements:
Java SE Development Kit 8 with update 121 or a more recent version 8 update. The same versions are supported with OpenJDK. Tanzu GemFire is compatible with Open JDK 11 (HotSpot).
An adequate per-user limit on the number of file descriptors; for Unix/Linux, the recommended soft limit is 8192, and the hard limit is 81920.
An adequate per-user limit on the number of processes (nproc); for Unix/Linux, the recommended soft limit is 501408, with an unlimited hard limit.
A system clock set to the correct time and a time synchronization service such as Network Time Protocol (NTP). Correct time stamps permit the following activities:
The host name and host files are properly configured for the machine. The host name and host file configuration can affect
gfsh and Pulse functionality.
Disable TCP SYN cookies. Most default Linux installations use SYN cookies to protect the system against malicious attacks that flood TCP SYN packets, but this feature is not compatible with stable and busy Tanzu GemFire clusters. Security implementations should instead seek to prevent attacks by placing Tanzu GemFire server clusters behind advanced firewall protection.
To disable SYN cookies permanently:
/etc/sysctl.conf file to include the following line:
net.ipv4.tcp_syncookies = 0
Setting this value to zero disables SYN cookies.