I'm getting a -1 value for CPU usage when connecting visual VM to my tomcat server.

2024-09-05 Thread Aditya Kumar
I have enabled JMX in my tomcat server. I use VisualVM to inspect the
tomcat server.

When I look at java.lang->OperatingSystem I'm seeing a -1 value for a few
CPU value readings. This just suddenly happened. I cant think what changes
might have been made, I don't recall any apart from maybe a Windows Update

[image: jmx.png]

The java version is Eclipse Temurin JDK version 17.0.11 build 17
Can anyone explain this or advise on how to debug further?

There was a report here about this issue. I tried going to JDK 18 but this
did not help.
https://bugs.openjdk.org/browse/JDK-8265104


Maximum header size in Tomcat 9

2022-05-25 Thread Aditya Kumar
Hi

I'm using Tomcat 9.0.46 and I want to know what is the maximum possible
value for maxHttpHeaderSize

I have Tomcat setup using kerberos authentication and for some users the
Authorisation header is too large (too many AD groups).

I have seen various articles when googling but I want something from
official documentation to state what the possible values for this field
are. Is it true that setting a value of "-1" causes a limitless maximum
header size value?


Re: Maximum header size in Tomcat 9

2022-05-25 Thread Aditya Kumar
I'm sorry I'm not sure what you mean by Integer.MAX_VALUE?

Looking at https://tomcat.apache.org/tomcat-9.0-doc/config/http.html all I
see is this:-
"maxHttpHeaderSize

The maximum size of the request and response HTTP header, specified in
bytes. If not specified, this attribute is set to 8192 (8 KB)."
This does not explain possible values. Can you give me an actual number for
the maximum?

Also I saw in this article:
https://community.jaspersoft.com/wiki/how-pass-big-number-values-apache-tomcat-url-string

" A value of less than 0 means no limit."


On Wed, May 25, 2022 at 10:19 AM Mark Thomas  wrote:

> On 25/05/2022 09:51, Aditya Kumar wrote:
> > Hi
> >
> > I'm using Tomcat 9.0.46 and I want to know what is the maximum possible
> > value for maxHttpHeaderSize
>
> Integer.MAX_VALUE
>
> > I have Tomcat setup using kerberos authentication and for some users the
> > Authorisation header is too large (too many AD groups).
> >
> > I have seen various articles when googling but I want something from
> > official documentation to state what the possible values for this field
> > are. Is it true that setting a value of "-1" causes a limitless maximum
> > header size value?
>
> Where did you read that? I don't see that in the documentation.
>
> Mark
>
> -
> To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org
> For additional commands, e-mail: users-h...@tomcat.apache.org
>
>


Re: Maximum header size in Tomcat 9

2022-05-25 Thread Aditya Kumar
Thanks! Sorry I misread that article.

So I suppose it's the same for maxHttpRequestHeaderSize and
maxHttpResponseHeaderSize?



On Wed, May 25, 2022 at 10:45 AM Mark Thomas  wrote:

> On 25/05/2022 10:33, Aditya Kumar wrote:
> > I'm sorry I'm not sure what you mean by Integer.MAX_VALUE?
>
> https://docs.oracle.com/javase/8/docs/api/java/lang/Integer.html#MAX_VALUE
>
> > Looking at https://tomcat.apache.org/tomcat-9.0-doc/config/http.html
> all I
> > see is this:-
> > "maxHttpHeaderSize
> >
> > The maximum size of the request and response HTTP header, specified in
> > bytes. If not specified, this attribute is set to 8192 (8 KB)."
> > This does not explain possible values. Can you give me an actual number
> for
> > the maximum?
>
> See above.
>
> The theoretical maximum is so far above any sensible value there is not
> much point documenting it.
>
> > Also I saw in this article:
> >
> https://community.jaspersoft.com/wiki/how-pass-big-number-values-apache-tomcat-url-string
> >
> > " A value of less than 0 means no limit."
>
> That text is copied directly from the Tomcat documentation and is part
> of the description for maxParameterCount, not maxHttpHeaderSize. What
> makes you think it might apply to maxHttpHeaderSize?
>
> Mark
>
>
> >
> >
> > On Wed, May 25, 2022 at 10:19 AM Mark Thomas  wrote:
> >
> >> On 25/05/2022 09:51, Aditya Kumar wrote:
> >>> Hi
> >>>
> >>> I'm using Tomcat 9.0.46 and I want to know what is the maximum possible
> >>> value for maxHttpHeaderSize
> >>
> >> Integer.MAX_VALUE
> >>
> >>> I have Tomcat setup using kerberos authentication and for some users
> the
> >>> Authorisation header is too large (too many AD groups).
> >>>
> >>> I have seen various articles when googling but I want something from
> >>> official documentation to state what the possible values for this field
> >>> are. Is it true that setting a value of "-1" causes a limitless maximum
> >>> header size value?
> >>
> >> Where did you read that? I don't see that in the documentation.
> >>
> >> Mark
> >>
> >> -
> >> To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org
> >> For additional commands, e-mail: users-h...@tomcat.apache.org
> >>
> >>
> >
>
> -
> To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org
> For additional commands, e-mail: users-h...@tomcat.apache.org
>
>


Apache Tomcat wire logging does not show POST data payload

2023-03-09 Thread Aditya Kumar
I edited my log4j2.xml to include these lines:





Now in my defined serverlog I see the http wire traffic I am after. However
there is one problem. For POST requests from my Tomcat server I can only
see request/response HTTP headers. I cannot see the POST data payload.

Is there a way to get this logged too?


How do I see the POST payload sent from Tomcat

2023-03-16 Thread Aditya Kumar
I have a Java application running under Tomcat 9. One component of this
application is OpenID authentication, in which my application is a relying
party.

It sends a POST request to https://login.microsoftonline.com, but  in one
scenario I'm getting an error back from Microsoft.

I need to see exactly what was sent in the POST request including the POST
payload data. Is there a way of doing this? I tried the requestdumper
filter but I don't see anything useful.


Why does Tomcat open connections on localhost?

2020-03-31 Thread Aditya Kumar
Tomcat 9.0.30 on Windows Server 2012 / Java 1.8

I've noticed on a freshly installed version of tomcat 9, upon startup there
are several connections to and from localhost on different ports

For example on my tomcat server there are 4 connections to and from
localhost (output from netstat)

 TCP0.0.0.0:8080   0.0.0.0:0  LISTENING   3972
 TCP127.0.0.1:55618127.0.0.1:55619ESTABLISHED 3972
 TCP127.0.0.1:55619127.0.0.1:55618ESTABLISHED 3972
 TCP127.0.0.1:55620127.0.0.1:55621ESTABLISHED 3972
 TCP127.0.0.1:55621127.0.0.1:55620ESTABLISHED 3972
 TCP[::]:8080  [::]:0 LISTENING   3972

These can grow to a large number (several thousand) on a busy system. What
are these connections used for? What caused them? What thread are they
attributed to?


Re: Why does Tomcat open connections on localhost?

2020-03-31 Thread Aditya Kumar
Hi Mark,

Sorry I'm not familiar with what a Selector is? However on one system I've
noticed 28000 such connections. Are these caused by client connections? I'm
not saying the connection originates from a client, but does the type of
socket get create because of client connections?

On Tue, Mar 31, 2020 at 1:20 PM Mark Thomas  wrote:

> On 31/03/2020 11:20, Aditya Kumar wrote:
> > Tomcat 9.0.30 on Windows Server 2012 / Java 1.8
> >
> > I've noticed on a freshly installed version of tomcat 9, upon startup
> there
> > are several connections to and from localhost on different ports
> >
> > For example on my tomcat server there are 4 connections to and from
> > localhost (output from netstat)
> >
> >  TCP0.0.0.0:8080   0.0.0.0:0  LISTENING
>  3972
> >  TCP127.0.0.1:55618127.0.0.1:55619ESTABLISHED
>  3972
> >  TCP127.0.0.1:55619127.0.0.1:55618ESTABLISHED
>  3972
> >  TCP127.0.0.1:55620127.0.0.1:55621ESTABLISHED
>  3972
> >  TCP127.0.0.1:55621127.0.0.1:55620ESTABLISHED
>  3972
> >  TCP[::]:8080  [::]:0 LISTENING
>  3972
> >
> > These can grow to a large number (several thousand) on a busy system.
> What
> > are these connections used for? What caused them? What thread are they
> > attributed to?
>
> The Java NIO implementation on Windows uses TCP for intra-process
> signalling. It opens a pair of self-connected sockets for every Selector.
>
> Mark
>
> -
> To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org
> For additional commands, e-mail: users-h...@tomcat.apache.org
>
>