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I have Tomcat7 installed on an AWS EC2 machine running Ubuntu 16.04. I start Tomcat7 on port 8080, and, from that same machine, can telnet to localhost 8080, execute "GET /", and see the index page.

However, when I telnet to it from a different machine, a connection is made, I can execute "GET /", but then the connection closes with no response. I know that it is connecting to the same server and service because I can find it on the server with netstat -an.

If I execute an invalid command, eg, "XYZZY /", I get the Tomcat error page, and an entry in the logs. But valid commands do not return any response, and do not show up in the logs.

Things I have done previous to posting here:

So how do I get Tomcat7 to start returning responses to the remote client?


server.xml (this was original 8080, but I changed it to test if it was a port conflict):

<Connector port="8085" protocol="HTTP/1.1" connectionTimeout="20000" URIEncoding="UTF-8" />

setenv.sh (based off of responses from previous questions that sounded vaguely similar; forces urandom for entropy, and IPv4 addresses):

JAVA_OPTS="$JAVA_OPTS -Djava.net.preferIPv4Stack=true -Djava.net.preferIPv4Addresses=true -Djava.security.egd=file:/dev/./urandom"

Local test:

xxx@xxx:~$ sudo /etc/init.d/tomcat7 restart
[ ok ] Restarting tomcat7 (via systemctl): tomcat7.service.
xxx@xxx:~$ telnet xxx 8085
Trying xxx...
Connected to xxx.
Escape character is '^]'.
GET /
<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
   "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
    <title>Apache Tomcat</title>
</head>

<body>
<h1>It works !</h1>
<snipped for brevity>
</body>
</html>
Connection closed by foreign host.

Remote test:

$ telnet xxx 8085
Trying xxx...
Connected to xxx.
Escape character is '^]'.
GET /
Connection closed by foreign host.

If instead of GET /, I issue XYZZY /:

$ telnet xxx 8085
Trying xxx...
Connected to xxx.
Escape character is '^]'.
XYZZY /
<html><head><title>Apache Tomcat/7.0.68 (Ubuntu) - Error report</title><style><!--H1 {font-family:Tahoma,Arial,sans-serif;color:white;background-color:#525D76;font-size:22px;} H2 {font-family:Tahoma,Arial,sans-serif;color:white;background-color:#525D76;font-size:16px;} H3 {font-family:Tahoma,Arial,sans-serif;color:white;background-color:#525D76;font-size:14px;} BODY {font-family:Tahoma,Arial,sans-serif;color:black;background-color:white;} B {font-family:Tahoma,Arial,sans-serif;color:white;background-color:#525D76;} P {font-family:Tahoma,Arial,sans-serif;background:white;color:black;font-size:12px;}A {color : black;}A.name {color : black;}HR {color : #525D76;}--></style> </head><body><h1>HTTP Status 501 - Method XYZZY is not implemented by this servlet for this URI</h1><HR size="1" noshade="noshade"><p><b>type</b> Status report</p><p><b>message</b> <u>Method XYZZY is not implemented by this servlet for this URI</u></p><p><b>description</b> <u>The server does not support the functionality needed to fulfill this request.</u></p><HR size="1" noshade="noshade"><h3>Apache Tomcat/7.0.68 (Ubuntu)</h3></body></html>Connection closed by foreign host.

So again I know that I am connecting to Tomcat.

If I do connect remotely but do not immediately issue a command, but instead on the local machine execute netstat -an | grep 8085, I get:

xxx:~$ netstat -an | grep 8085
tcp        0      0 0.0.0.0:8085            0.0.0.0:*               LISTEN
tcp        0      0 xxx:8085                yyy:52329               ESTABLISHED

Where yyy is my remote address, so I know that the connection is occurring correctly.

1 Answer 1

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Disappointingly, the problem was a firewall doing port verification and thus killing the requests. So anything starting with "GET " was being blocked outbound, which is why I was seeing the results I did. Changed it to port 80 and suddenly everything works.

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