我在配置跨集群数据同步时候。A集群需要从B集群同步数据，但是B集群是带有安全认证的。所以需要把B集群的证书放在A集群。
为了偷懒，我把elastic-certificates.p12 证书，放在了config目录的外边。然后就报了下边的错。一开始我以为没有读权限，所以就 使用 chmod 777 elastic-certificates.p12 但是已经不能使用。
后台把文件挪到了config目录下，然后又修改elasticsearch.yml 里边的配置路径，使用了elastic-certificates.p12的绝对路径，然后就能成功启动了。
Caused by: java.security.AccessControlException: access denied ("java.io.FilePermission" "/home/wsn/es7.3/cert/elastic-certificates.p12" "read") at java.security.AccessControlContext.checkPermission(AccessControlContext.java:472) ~[?:?] at java.security.AccessController.checkPermission(AccessController.java:1044) ~[?:?] at java.lang.SecurityManager.checkPermission(SecurityManager.java:408) ~[?:?] at java.lang.SecurityManager.checkRead(SecurityManager.java:747) ~[?:?] at sun.nio.fs.UnixPath.checkRead(UnixPath.java:818) ~[?:?] at sun.nio.fs.UnixFileSystemProvider.checkAccess(UnixFileSystemProvider.java:295) ~[?:?] at java.nio.file.Files.notExists(Files.java:2565) ~[?:?] at org.elasticsearch.common.ssl.KeyStoreUtil.readKeyStore(KeyStoreUtil.java:72) ~[?:?] at org.elasticsearch.common.ssl.StoreKeyConfig.createKeyManager(StoreKeyConfig.java:69) ~[?:?] at org.elasticsearch.common.ssl.SslConfiguration.createSslContext(SslConfiguration.java:135) ~[?:?] at org.elasticsearch.index.reindex.ReindexSslConfig.reload(ReindexSslConfig.java:145) ~[?:?] at org.elasticsearch.index.reindex.ReindexSslConfig.(ReindexSslConfig.java:115) ~[?:?] at org.elasticsearch.index.reindex.ReindexPlugin.createComponents(ReindexPlugin.java:88) ~[?:?] at org.elasticsearch.node.Node.lambda$new$9(Node.java:457) ~[elasticsearch-7.3.1.jar:7.3.1] at java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:271) ~[?:?] at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1654) ~[?:?] at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484) ~[?:?] at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474) ~[?:?] at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:913) ~[?:?] at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) ~[?:?] at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:578) ~[?:?] at org.elasticsearch.node.Node.(Node.java:460) ~[elasticsearch-7.3.1.jar:7.3.1] at org.elasticsearch.node.Node.(Node.java:258) ~[elasticsearch-7.3.1.jar:7.3.1] at org.elasticsearch.bootstrap.Bootstrap$5.(Bootstrap.java:221) ~[elasticsearch-7.3.1.jar:7.3.1] at org.elasticsearch.bootstrap.Bootstrap.setup(Bootstrap.java:221) ~[elasticsearch-7.3.1.jar:7.3.1] at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:349) ~[elasticsearch-7.3.1.jar:7.3.1] at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:159) ~[elasticsearch-7.3.1.jar:7.3.1] ... 6 more
