Wildfly Connection refused for url with DNS name - wildfly

I have a Wildfly 16 instance running on a test server. This instance can be reached successfully via the host name and the IP address of the server. In addition, there is a DNS entry for the server similar to test.mydomain.internal. The server does not respond to the DNS name (example url: http://test_instance.mydomain.internal:8080/test/). The connection is refused.
What do I have to set in the standalone.xml so that I can also get a connection via the DNS name?
-update-
The sample url has been adjusted to clarify the problem in the question .

I found the problem. It had nothing to do with the settings in the Wildfly. The DNS entry had underlines in the name. SOAPUI and two other programs had a problem with that.

Related

Remote EJB in Kubernetes

I'm trying to setup a remote EJB call between 2 WebSphere Liberty servers deployed in k8s.
Yes, I'm aware that EJB is not something one would want to use when deploying in k8s, but I have to deal with it for now.
The problem I have is how to expose remote ORB IP:port in k8s. From what I understand, it's only possible to get it to work if both client and remote "listen" on the same IP. I'm not a network expert, and I'm quite fresh in k8s, so maybe I'm missing something here, that's why I need help.
The only way I got it to work is when I explicitly set host on remote server to it's own IP address and then accessed it from client on that same IP. This test was done on Docker host with macvlan0 network (each container had it's own IP address).
This is ORB setup for remote server.xml configuration:
<iiopEndpoint id="defaultIiopEndpoint" host="172.30.106.227" iiopPort="2809" />
<orb id="defaultOrb" iiopEndpointRef="defaultIiopEndpoint">
<serverPolicy.csiv2>
<layers>
<!-- don't care about security at this point -->
<authenticationLayer establishTrustInClient="Never"/>
<transportLayer sslEnabled="false"/>
</layers>
</serverPolicy.csiv2>
</orb>
And client server.xml configuration:
<orb id="defaultOrb">
<clientPolicy.csiv2>
<layers>
<!-- really, I don't care about security -->
<authenticationLayer establishTrustInClient="Never"/>
<transportLayer sslEnabled="false"/>
</layers>
</clientPolicy.csiv2>
</orb>
From client, this is JNDI name I try to access it:
corbaname::172.30.106.227:2809#ejb/global/some-app/ejb/BeanName!org\.example\.com\.BeanRemote
And this works.
Since one doesn't want to set fixed IP when exposing ORB port, I have to find a way to expose it dynamically, based on host IP.
Exposing on 0.0.0.0 does not work. Same goes for localhost. In both cases, client refuses to connect with this kind of error:
Error connecting to host=0.0.0.0, port=2809: Connection refused (Connection refused)
In k8s, I've exposed port 2809 through LoadBalancer service for remote pods, and try to access remote server from client pod, where I've set remote's service IP address in corbaname definition.
This, of course, does not work. I can access remote ip:port by telnet, so it's not a network issue.
I've tried all combinations of setup on remote server. Exporting on host="0.0.0.0" results with same exception as above (Connection refused).
I'm not sure exporting on internal IP address would work either, but even if it would, I don't know the internal IP before pod is deployed in k8s. Or is there a way to know? There is no env. variable with it, I've checked.
Exposing on service IP address (with host="${REMOTE_APP_SERVICE_HOST}") fails with this error:
The server socket could not be opened on 2,809. The exception message is Cannot assign requested address (Bind failed).
Again, I know replacing EJB with Rest is the way to go, but it's not an option for now (don't ask why).
Help, please!
EDIT:
I've managed to get some progress. Actually, I believe I've successfully called remote EJB.
What I did was add hostAliases in pod definition, which added alias for my host, something like this:
hostAliases:
- ip: 0.0.0.0
hostnames:
- my.host.name
Then I added this host name to remote server.xml:
<iiopEndpoint id="defaultIiopEndpoint" host="my.host.name" iiopPort="2809" />
I've also added host alias to my client pod:
hostAliases:
- ip: {remote.server.service.ip.here}
hostnames:
- my.host.name
Finally, I've changed JNDI name to:
corbaname::my.host.name:2809#ejb/global/some-app/ejb/BeanName!org\.example\.com\.BeanRemote
With this setup, remote server was successfully called!
However, now I have another problem which I didn't have while testing on Docker host. Lookup is done, but what I get is not what I expect.
Lookup code is pretty much what you'd expect:
Object obj = new InitialContext().lookup(jndi);
BeanRemote remote = (BeanRemote) PortableRemoteObject.narrow(obj, BeanRemote.class);
Unfortunatelly, this narrow call fails with ClassCastException:
Caused by: java.lang.ClassCastException: org.example.com.BeanRemote
at com.ibm.ws.transport.iiop.internal.WSPortableRemoteObjectImpl.narrow(WSPortableRemoteObjectImpl.java:50)
at [internal classes]
at javax.rmi.PortableRemoteObject.narrow(PortableRemoteObject.java:62)
Object I do receive is org.omg.stub.java.rmi._Remote_Stub. Any ideas?
Solved it!
So, the first problem was resolving host mapping, which was resolved as mentioned in edit above, by adding host aliases id pod definitions:
Remote pod:
hostAliases:
- ip: 0.0.0.0
hostnames:
- my.host.name
Client pod:
hostAliases:
- ip: {remote.server.service.ip.here}
hostnames:
- my.host.name
Remote server then has to use that host name in iiop host definition:
<iiopEndpoint id="defaultIiopEndpoint" host="my.host.name" iiopPort="2809" />
Also, client has to reference that host name through JNDI lookup:
corbaname::my.host.name:2809#ejb/global/some-app/ejb/BeanName!org\.example\.com\.BeanRemote
This setup resolves remote EJB call.
The other problem with ClassCastException was really unusual. I managed to reproduce the error on Docker host and then changed one thing at a time until the problem was resolved. It turns out that the problem was with ldapRegistry-3.0 feature (!?). Adding this feature to client's feature list resolved my problem:
<feature>ldapRegistry-3.0</feature>
With this feature added, remote EJB was successfully called.

dns configuration for openfire xmpp server

I want to use XMPP server in my app to handle messages but I'm having issues configuring my server. When I login to my Openfire admin panel I get a warning telling me that my DNS configuration appears to be missing or incorrect. My question now is, how can I create DNS SRV records for my host? I have searched all over the net for a solution but none helped me.
My openfire admin page.
the value for the xmpp.fqdn property should be the full network name of the server that is running Openfire, the name that clients would use to connect to Openfire.Maybe your current value is incorrect and you have to edit it.
you can edit fqdn under system properties
That error in Admin Console means that DNS managing records for dialup.org domain doesn't have a SRV record pointing to XMPP service. It seems that you have installed Openfire on a regular desktop and expect it to work on the Internet. For this you have to have some internet domain and have proper DNS records on that domain.

unable to connect to openfire server with external ip

I'm trying to connect to openfire server using spark. I have dynamic dns, made port forwarding on port 5222 in d-link router. When i'm logging with host name as private ip for example "192.168.0.101" - connection is established, but when i'm setting my domain (pizokas.hopto.org) as host name i get the following error
Unknown connection error. Please review logs for the following information.
But there are no logs in openfire server, so i assume packets are dropped in router. I have firewall turned off. At this point i can't find information why the connection cannot be established. I'm using my own laptop as server and as a client, os win 10. Maybe somebody had similar issue?
The connection was established when i was trying to connect to server from outside of lan

getting SocketTimeoutException while using smack 4.1.2 in android to connect to my ejabberd server

I am trying to connect to ejabberd server using smack API 4.1.2 (no asmack) on android device. while running smackClient program , I am getting below error
java.net.SocketTimeOutException:Failed to connect to abc.example.com/182.*.*.* (on port 5222) after 30000ms,'abc.example.com:5222' failed because java.net.ConnectionException: Failed to connect to abc.example.com/182.*.*.* (on port 5222) after 30000ms
Connection to same ejabberd server using same android device is working fine using xmpp clients like xabber. so Issue is surely with client code I have written. Below is the snippet of my code
XMPPTCPConnectionConfiguration config = XMPPTCPConnectionConfiguration.builder()
.setUsernameAndPassword(userName, password)
.setServiceName("abc.example.com")
.setSecurityMode(ConnectionConfiguration.SecurityMode.disabled)
.setSendPresence(true)
.build();
connection = new XMPPTCPConnection(config);
connection.connect();
connection.login(userName, password);
I am missing something in my client code that xabber is having so xabber connection is working from same device using same credential.
Please help
Hard to tell without real IP and names in your example. However, my best guess would be about how the address to your IP server is resolved.
There seems to be discrepancy in your example with server (example.com) and service name in your code (abc.example.com).
My guess it that your client is attempting to connect to another machine that the one the XMPP server is running on.
So, here are the things to check when you have issues with a server not replying:
Check how the address of the domain is resolved. You may need to specify another machine name that the domain. If this is a test domain, there is possibly not a DNS setup, so you may even need to specify server IP (while still configuring the client to use an XMPP domain, that's two different things).
In client, log the IP you are trying to connect to, to make sure this is the one where the server is running.
If server is not on the main domain server, you may even need to do DNS SRV record queries for XMPP C2S service.
For me , it took hours to find the solution.
I forget to turnoff the VPN application(Express VPN) .Network tunneling was the root cause .
And change the Network protocol version properties as below ,
Choose the 1st option (Obtain DNS server address automatically).
My experience: I used following code
DomainBareJid xmppServiceDomain = JidCreate.domainBareFrom("desktop-urvfr83");
//DomainBareJid xmppServiceDomain = JidCreate.domainBareFrom("192.168.1.3");
InetAddress addr = InetAddress.getByName("192.168.1.3");
XMPPTCPConnectionConfiguration config = XMPPTCPConnectionConfiguration.builder()
.setUsernameAndPassword("alir", "111111")
.setHostAddress(addr)
.setResource("phonn")
.setXmppDomain(xmppServiceDomain)
.setSecurityMode(ConnectionConfiguration.SecurityMode.disabled)
.setPort(5222)
.build();
but it could not connect and produced timeout connection exception. When I disabled windows firewall it worked correctly and connected.

Resolve hostname to IP address for Postfix

I'm trying to setup postfix in a VPC on AWS where an external server communicates with a postfix mail server in the same subnet.
I'm getting an error from postfix every time I try to connect to postfix from an external client. The error says:
warning: hostname example.com does not resolve to address 54.x.xxx.xxx
connect from unknown[54.x.xxx.xxx]
lost connection after CONNECT from unknown[54.x.xxx.xxx]
I'm suspecting this is related to the IP address that is being pointed to the hostname. When I run:
dig example.com
The 'answer' section outputs this:
;; ANSWER SECTION:
example.com. 60 IN A 10.0.1.132
I've looked at this link: http://www.postfix.org/LINUX_README.html
and I've tried editing /etc/host.conf and the /etc/postfix/main.cf file from that link and a bunch of other things from googling but nothing is working and I still get the same error mentioned above.
Is there a way to configure the VPC or the EC2 instance to point to my public IP address, or can I fix this problem trying to add some more configuration settings for postfix?