Develop Reference

"Server Tomcat v9.0 Server at localhost failed to start" without any stack trace

I keep getting this error while I try to start Tomcat in Eclipse. No other message or details just a pop up with this message: "Server Tomcat v9.0 Server at localhost failed to start." Tomcat works fine in the terminal so I don't see what could be the issue. I looked at countless solutions, nothing worked.
What I tried:
- Changing the ports
- Reinstalling server
- Deleting .snap file
- Deleting temp folder
- Removing runtime environment
- Restarting everything
So basically all the suggestions that were made in different posts, nothing works, anybody have any idea what else can I try?
Ps. It can't be the web.xml since I get the same message when I try to start the tomcat server on it's own without any project.
Can it be some permission issues somewhere in windows?

error resolving localhost while running java servlets in eclipse's browser

I am new to java servlets. I have installed apache-tomcat-9.0.0.M21.
When I run the project containing servlet in eclipse browser, sometimes I get the error-
Error resolving 'localhost': Name or service not known.
Other times the error is -
Error resolving 'localhost' : Temporary failure in name resolution.
This project runs fine in my web browser.
Also, after I add <servlet>...</servlet> and <servlet-mapping>...<servlet-mapping> in web.xml, I get the error - Server Tomcat v9.0 Server at localhost failed to start.
One more thing, I use Ubuntu operating system (if it has to do something with the question).
Please help. I googled for the solution but I am not able to resolve the error.

Try adding the below to your /etc/hosts file.
127.0.0.1 localhost

Run JHipster in production profile - no database connection

I have a problem with running JHipster in Production Mode. After building the .war by
mvn -Pprod package
and uploading it to my server, I get the "normal" start page - so the page loaded, but with following errors:
"NetworkError: 404 Not Found - http://server.net:9080/studentenhelfer-intern-0.0.1-SNAPSHOT.original/api/authentication?cacheBuster=1459611519471"
"NetworkError: 404 Not Found - http://server.net:9080/studentenhelfer-intern-0.0.1-SNAPSHOT.original/api/logout?cacheBuster=1459611519626"
The second point - when I "install/start" the Application on the server, the database will be not created. (No tables and no data)
I can´t figure out why.... With the dev-profile everything is working fine.... (Also with the same DB settings in application-prod.yml)
Additionial Info: the spring profile has also been set to prod profile in
/etc/default/tomcat7
JAVA_OPTS="${JAVA_OPTS} -Dspring.profiles.active=prod"
(This should be ok, yes?)
I´m using MySql as Db (with liquibase) and Maven for building. The server is a linux server (ubuntu) with Plesk 12.
For information - that´s my first experience with a linux-server. So maybe I forgot some extra configurations, but I think if the page gets loaded, the tomcat should not be the problem)
I also can´t find any "usefull" logs from catalina or tomcat...
var/log/tomcat7/catalina.out
var/log/apache2/error.log
But if someone needs to see the logs, I will post them..
Please help :(
Thanks, Fab
EDIT: I have tried to run the application on a local running tomcat -> And it works... so it´s a server-side problem?

Facing 404 error after upgraded to Tomcat 7.0.54

Recently I have upgraded the tomcat version from 7.0.26 to 7.0.54, and now I am facing 404 error with tomcat 7.0.54 version.
I have tested with most of the version, till tomcat 7.0.53 my product help link works fine. I am not sure what change had made in 7.0.54 version.
Actual Issue:
We have simple main_help.war file which is integrated in my product and on click on help link it launches new tab and shows html page runs on java.
This is the actual URL - https://hostname.com:8444/main_help/help_services/html/admin_en_usa/index.htm?URL=admin_1_0_0/help_wrapper_topic.html&SHOWTOC=1&CHROME=false
with no change in our product and just updated tomcat to 7.0.54 version, the URL is not coming properly. main_help (which is the main war deployed in server (main_help.war)) string is missing in the URL.
This is the URL after upgraded to tomcat 7.0.54 - https://hostname.com:8444//help_services/html/admin_en_usa/index.htm?URL=admin_1_0_0/help_wrapper_topic.html&SHOWTOC=1&CHROME=false
OS Detail:
- Windows 7 64bit.
- Java 7
- All browser type (same issue)
Could someone please help me what is the change that Apache made? And how can I modify my application accordingly.
Regards
Thiru

FileNotFoundException while running SolrCloud on Tomcat

I have a Solr 4.2.0 server which is running under the Tomcat 7.0 container. I'm trying to wire it with my external zookeeper (actually, it doesn't work with the embdedded zookeeper too).
I tried this java opts:
-Dbootstrap_confdir=./solr/collection1/conf
-Dcollection.configName=myconf
-DzkRun
-DnumShards=2
for running the embedded zookeeper.
And also this java opts:
-Dbootstrap_confdir=./solr/collection1/conf
-Dcollection.configName=myconf
-DzkHost=localhost:2181
-DnumShards=2
For connecting to external zookeeper
In both cases I continue to get the same exception:
java.io.FileNotFoundException: File '.\solr\collection1\conf \admin-extra.html' does not exist
But the problem is that file admin-extra.html exists and it's right here. And I can't figure out what the problem is.

From your exception it seems your path has a white space after the config directory.
Try to define your bootstrap_configdir between "", like:
-Dbootstrap_confdir="./solr/collection1/conf"