Caused by: org.apache.catalina.LifecycleException: A child container failed during start
    at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:950) ~[tomcat-embed-core-8.5.34.jar!/:8.5.34]
    at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:872) ~[tomcat-embed-core-8.5.34.jar!/:8.5.34]
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) ~[tomcat-embed-core-8.5.34.jar!/:8.5.34]
    ... 6 common frames omitted
Caused by: java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[]]
    at java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[na:1.8.0_121]
    at java.util.concurrent.FutureTask.get(FutureTask.java:192) ~[na:1.8.0_121]
    at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:942) ~[tomcat-embed-core-8.5.34.jar!/:8.5.34]
    ... 8 common frames omitted
Caused by: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[]]
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:167) ~[tomcat-embed-core-8.5.34.jar!/:8.5.34]
    ... 6 common frames omitted
Caused by: org.apache.catalina.LifecycleException: Failed to start component [org.apache.catalina.webresources.StandardRoot@3a147ae1]
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:167) ~[tomcat-embed-core-8.5.34.jar!/:8.5.34]
    at org.apache.catalina.core.StandardContext.resourcesStart(StandardContext.java:4907) ~[tomcat-embed-core-8.5.34.jar!/:8.5.34]
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5042) ~[tomcat-embed-core-8.5.34.jar!/:8.5.34]
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) ~[tomcat-embed-core-8.5.34.jar!/:8.5.34]
    ... 6 common frames omitted
Caused by: java.lang.IllegalArgumentException: The main resource set specified [/tmp/tomcat-docbase.6227775345915450173.2222] is not valid
    at org.apache.catalina.webresources.StandardRoot.createMainResourceSet(StandardRoot.java:748) ~[tomcat-embed-core-8.5.34.jar!/:8.5.34]
    at org.apache.catalina.webresources.StandardRoot.startInternal(StandardRoot.java:706) ~[tomcat-embed-core-8.5.34.jar!/:8.5.34]

最后发现是磁盘满了，
使用下面的命令查看磁盘使用情况

df -h

发现/dev/vda1 磁盘占用100%，然后查看/tmp日志的情况

 du -sh /tmp

发现spring cloud gateway 占用了大量的日志文件
删掉后，发现并没有减少，使用命令

 lsof | grep delete

发现这些删除，但是被程序占用了的文件，只有新启动gateway 程序，日志文件才被删除，解决。