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| private boolean doFence(Session session, InetSocketAddress serviceAddr)
throws JSchException {
int port = serviceAddr.getPort();
try {
//这段日志已经出现，所以忽略
LOG.info("Looking for process running on port " + port);
int rc = execCommand(session,
"PATH=$PATH:/sbin:/usr/sbin fuser -v -k -n tcp " + port);
//这段日志没出现，所以代表执行该命令返回值为rc == 1
if (rc == 0) {
LOG.info("Successfully killed process that was " +
"listening on port " + port);
// exit code 0 indicates the process was successfully killed.
return true;
} else if (rc == 1) {
// exit code 1 indicates either that the process was not running
// or that fuser didn't have root privileges in order to find it
// (eg running as a different user)
LOG.info(
"Indeterminate response from trying to kill service. " +
"Verifying whether it is running using nc...");
//然后通过这个命令去检查端口是否还在的时候，报错了，返回2,并不是执行返回１,而是执行方法有误
rc = execCommand(session, "nc -z " + serviceAddr.getHostName() +
" " + serviceAddr.getPort());
if (rc == 0) {
// the service is still listening - we are unable to fence
LOG.warn("Unable to fence - it is running but we cannot kill it");
return false;
} else {
LOG.info("Verified that the service is down.");
return true;
}
} else {
// other
}
LOG.info("rc: " + rc);
return rc == 0;
} catch (InterruptedException e) {
LOG.warn("Interrupted while trying to fence via ssh", e);
return false;
} catch (IOException e) {
LOG.warn("Unknown failure while trying to fence via ssh", e);
return false;
}
}
|