切换为root用户操作，避免权限不足无法修改。

1.max file descriptors [4096] for elasticsearch process is too low, increase to at least [65536]

vi /etc/security/limits.conf
* soft nofile 65536
* hard nofile 65536

注：修改完需要重启linux。

2.max number of threads [3818] for user [esuser] is too low, increase to at least [4096]

vi /etc/security/limits.d/90-nproc.conf
* soft nproc 4096
* hard nproc 4096

注：上面的**[esuser]**方括号里的为启动elasticsearch服务的用户名。

3.max virtual memory areas vm.max_map_count [65530] is too low, increase to at least [262144]

vi /etc/sysctl.conf
vm.max_map_count=262144

注：修改完执行sysctl -p命令使改动生效。

4.system call filters failed to install; check the logs and fix your configuration or disable system call filters at your own risk

vi elasticsearch.yml
bootstrap.memory_lock: false
bootstrap.system_call_filter: false

注：这两行属性设置的顺序不能颠倒

5.the default discovery settings are unsuitable for production use; at least one of [discovery.seed_hosts, discovery.seed_providers, cluster.initial_master_nodes] must be configured

vi elasticsearch.yml
cluster.initial_master_nodes: ["node-1"]