Re[2]: Reverse DNS lookup
Friday, July 06, 2001, 7:02:45 AM, [EMAIL PROTECTED] wrote: RL The InetAddress...getHostName() call will use the DNS databases. RL For most computers, however, this won't return anything useful. That is not true. Most of US IPs have PTR records. That includes your own IP, that you had when sending your msg. By far, most servers have rDNS, most dynamic IPs do, most static IPs for cable/DSL do, and even most routers do. Asia (particularly Taiwan, China and Korea) is probably the worst, as far as being able to to rDNS. But even they might be a little over 50%, especially Japan. RL Randy -Original Message- From: David Wall [mailto:[EMAIL PROTECTED]] Sent: Friday, July 06, 2001 12:02 AM To: [EMAIL PROTECTED] Subject: Re: Reverse DNS lookup InetAddress.getByName(ip address).getHostName() will do what you want, if the info is available. Where would the info have to be available? Is there anything comparable to a dig -x command under Unix? For most IP addresses, there will not be anything configured on my computer, but I know that ARPA reverse lookups are possible. The method you show above still returns the IP address on my system, yet a dig -x will show the host name resolved. David
Re: creating a instance of a servlet: takes too long!!
Friday, July 06, 2001, 5:01:37 AM, [EMAIL PROTECTED] wrote: ps Greetings, ps why is that my servlet when the first time is invoked, it takes about 30 ps seconds or more to start when the servlets that came in tomcat are ps instantaneous? After the servlet container instantiated and initialized my ps servlet, all the following requests are very fast. Is there any advice for ps what we should do and don't do in init() method? I just initialize some ps properties and a connection pool ps Well is it possible that my servlet container at any time my may shutdown my ps servlet to release memory, and another time it will be requested to start ps again and take another time too long to start, correct? ps How can I benchmark the time of instantiation of my servlet and the time of ps my init method? ps System configuration: ps -Tomcat 3.2.1 ps -JDK 1.3 ps -Linux RedHat 6.2 [kernel 2.2.18] ps -PII400Mhz 256Mbytes ps thanks. ps -- ps psalazar/
Re: creating a instance of a servlet: takes too long!!
If your servlet has changed and needs to be recompiled, then using jikes instead of javac will save a lot of time. Friday, July 06, 2001, 5:01:37 AM, [EMAIL PROTECTED] wrote: ps Greetings, ps why is that my servlet when the first time is invoked, it takes about 30 ps seconds or more to start when the servlets that came in tomcat are ps instantaneous? After the servlet container instantiated and initialized my ps servlet, all the following requests are very fast. Is there any advice for ps what we should do and don't do in init() method? I just initialize some ps properties and a connection pool ps Well is it possible that my servlet container at any time my may shutdown my ps servlet to release memory, and another time it will be requested to start ps again and take another time too long to start, correct? ps How can I benchmark the time of instantiation of my servlet and the time of ps my init method? ps System configuration: ps -Tomcat 3.2.1 ps -JDK 1.3 ps -Linux RedHat 6.2 [kernel 2.2.18] ps -PII400Mhz 256Mbytes ps thanks. ps -- ps psalazar/
Re[2]: creating a instance of a servlet: takes too long!!
Friday, July 06, 2001, 10:16:05 AM, [EMAIL PROTECTED] wrote: PD There's another reason for this and it has to do with the java.security.SecureRandom class. From what I can tell, tomcat uses this class to generate a seed value for the PD session ID. The first request for a SecureRandom value (eg. new SecureRandom().nextLong()) can take many, many seconds to complete. After the PD first usage however, it returns immediately. I'm not sure what goes on when PD SecureRandom initializes but that seems to be where the slow down occurs. Yes, good point. I've just been looking at that, too. It reminds me of the time required to create a secure socket factory when using JSSE. After that time is initially spent, any other new sockets are created quickly. For development, I change to using randomClass=java.util.Random ..and have noticed that the attribute randomFile=/dev/urandom is irrelevant on win '98 (I assume this file contains a seed for the random generation?) Also, there seems to be a lot elsewise going on under the hood. When accessing a jsp, Tomcat seems to me (at this point) to be compiling servlets in the webapp. Can anybody elaborate on that? PD As a work around, you could create a low priority thread that instantiates a PD SecureRandom calls nextLong() then exits, and have this thread get launched by PD the init() method of a servlet that gets preloaded. This solution worked for me. PD Regards, PD Pete. PD Thus spake pedro salazar [EMAIL PROTECTED] on Fri, 6 Jul 2001 10:01:37 +0100: PS Greetings, PS PS why is that my servlet when the first time is invoked, it takes about 30 PS seconds or more to start when the servlets that came in tomcat are PS instantaneous? After the servlet container instantiated and initialized my PS servlet, all the following requests are very fast. Is there any advice for PS what we should do and don't do in init() method? I just initialize some PS properties and a connection pool PS Well is it possible that my servlet container at any time my may shutdown my PS servlet to release memory, and another time it will be requested to start PS again and take another time too long to start, correct? PS PS How can I benchmark the time of instantiation of my servlet and the time of PS my init method? PS PS System configuration: PS -Tomcat 3.2.1 PS -JDK 1.3 PS -Linux RedHat 6.2 [kernel 2.2.18] PS -PII400Mhz 256Mbytes PS PS thanks. PS -- PS psalazar/ PS PS
Re: can't find tomcat.jar ? [solved]
For the archives: this problem only occurs when using Jikes. By setting JIKES_PATH to include ...\lib\tomcat.jar the problem is solved. Friday, July 06, 2001, 12:05:30 AM, [EMAIL PROTECTED] wrote: wmc A fresh install of 3.3-m4 (with jdk1.4 on '98), and when I try to access a wmc jsp I get an error on finding C:\tomcat\lib\tomcat.jar. And wmc C:\tomcat\lib\tomcat.jar does exist. Thanks for any help. wmc org.apache.jasper.JasperException: Unable to compile wmc Found 2 system errors: wmc *** Error: Could not find package named: wmc C:\tomcat\lib\tomcat.jar(java/util), wmc C:\tomcat\work\DEFAULT\security/java/util, wmc C:\tomcat\lib\common\jasper34_runtime.jar(java/util), wmc C:\tomcat\lib\common\jasper-runtime.jar(java/util), wmc C:\tomcat\lib\common\core_util.jar(java/util), wmc C:\tomcat\lib\common\connector_util.jar(java/util), wmc C:\tomcat\lib\common\servlet.jar(java/util) or wmc C:\tomcat\lib\common\tomcat_core.jar(java/util) wmc *** Error: Could not find package named: wmc C:\tomcat\lib\tomcat.jar(java/lang), wmc C:\tomcat\work\DEFAULT\security/java/lang, wmc C:\tomcat\lib\common\jasper34_runtime.jar(java/lang), wmc C:\tomcat\lib\common\jasper-runtime.jar(java/lang), wmc C:\tomcat\lib\common\core_util.jar(java/lang), wmc C:\tomcat\lib\common\connector_util.jar(java/lang), wmc C:\tomcat\lib\common\servlet.jar(java/lang) or wmc C:\tomcat\lib\common\tomcat_core.jar(java/lang)
Re[4]: Reverse DNS lookup
Friday, July 06, 2001, 12:15:19 PM, [EMAIL PROTECTED] wrote:
RL The InetAddress...getHostName() call will use the DNS
DW databases.
RL For most computers, however, this won't return anything useful.
That is not true. Most of US IPs have PTR records. That includes your
own IP, that you had when sending your msg. By far, most servers have
DW rDNS,
most dynamic IPs do, most static IPs for cable/DSL do, and even most
DW routers
do.
DW The IP address I was testing is 216.122.43.90 and I am able to do a reverse
DW lookup using dig from the webserver. It just seems to me that the
DW InetAddress class is perhaps not using whatever it needs to do to use DNS.
DW Does anybody know what the implementation of InetAddress is actually doing
DW under the hood?
Well, the InetAddress methods do work correctly, Dave. Here is a quick demo:
import java.net.*;
public class IPGet {
public static void main(String[] args) {
try {
System.out.println(InetAddress.getByName(args[0]).getHostName());
} catch (Exception e) {
System.out.println(e);
}
}
}
and the console:
C:\testjikes -nowarn IPGet.java
C:\testjava IPGet 216.122.43.90
r90-43-dsl.sea.lightrealm.net
Now, for the kicker... On one run I got the same return as you
did: the IP number instead of hostname - this happens when the lookup
fails. Therefore, I would guess right now that here might be some problem
in the nameservers at lightrealm.
So, a partial dig shows:
Dig [EMAIL PROTECTED] ...
Authoritative Answer
Recursive queries supported by this server
Query for 90.43.122.216.in-addr.arpa type=255 class=1
90.43.122.216.in-addr.arpa PTR (Pointer) r90-43-dsl.sea.lightrealm.net
43.122.216.in-addr.arpa NS (Nameserver) ns1.lightrealm.net
and next:
07/06/01 12:50:19 ping ns1.lightrealm.net
Ping failed, no such host
That looks like a slam dunk. Lightrealm's problem, when they
periodically can't resolve within their domain. Not a Java problem.
HTH.
DW David
Re: RES: filtering IP's on Tomact
Friday, July 06, 2001, 1:08:12 PM, [EMAIL PROTECTED] wrote: JEdSJDO -BEGIN PGP SIGNED MESSAGE- JEdSJDO I think its impossible, since tomcat isnt a firewall.or even a webserver. It seems the most you can do is accept or deny from within the servlet, with getRemoteAddr(). JEdSJDO José Euclides Júnior JEdSJDO __ JEdSJDO E-mail: [EMAIL PROTECTED] JEdSJDO [EMAIL PROTECTED] JEdSJDO http://euclides.8m.com JEdSJDO - -Mensagem original- JEdSJDO De: Alberto Torna Jr. [SMTP:[EMAIL PROTECTED]] JEdSJDO Enviada em: Quinta-feira, 5 de Julho de 2001 15:37 JEdSJDO Para: [EMAIL PROTECTED] JEdSJDO Assunto:Re: filtering IP's on Tomact JEdSJDO What do you mean by filtering? From: Paulo Roque Reply-To: [EMAIL PROTECTED] To: [EMAIL PROTECTED] Subject: filtering IP's on Tomact Date: Thu, 05 Jul 2001 16:35:35 - Hi, Could anyone enlight me about if it is possible to filter a set of IP addresses on Tomcat 3.2.1 ? Thanks! Paulo Costa Portugal
Re[2]: Problem with stopping Tomcat
Friday, July 06, 2001, 2:47:01 PM, [EMAIL PROTECTED] wrote: -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] Sent: Friday, July 06, 2001 3:10 PM To: [EMAIL PROTECTED] Subject: Re: Problem with stopping Tomcat I thought 3.2.2 could use AJP13 instead? Am I wrong on that? RL My understanding is Tomcat 3.1-3 could only use AJP12 to shutdown, RL maybe you should post to the tomcat-dev list and let us know what you find RL out. The doc agrees with you: http://jakarta.apache.org/tomcat/tomcat-3.2-doc/mod_jk-howto.html The servlet.xml file already has a block similar to this for Ajp12 connections on port 8007 (as delivered by mod_jserv). Even if you think you're only using Ajp13, you probably don't want to delete this connector - it's required to shut down Tomcat.
generic exceptions on startup
This is a partial list of exceptions that I'm getting at startup (Win 98, 3.2.1). Anybody know what's going on? TOMCAT_HOME is properly set to C:\tomcat Not Apache nor IIS nor NS (whatever that is) are not involved in my setup at all. Thanks. java.lang.Exception at org.apache.tomcat.core.ContextManager.getHome(ContextManager.java:224 ) at org.apache.tomcat.core.ContextManager.getAbsolute(ContextManager.java :1512) at org.apache.tomcat.context.LoaderInterceptor.contextInit(LoaderInterce ptor.java:111) at org.apache.tomcat.core.ContextManager.initContext(ContextManager.java :491) at org.apache.tomcat.core.ContextManager.init(ContextManager.java:453) at org.apache.tomcat.startup.Tomcat.execute(Tomcat.java:195) at org.apache.tomcat.startup.Tomcat.main(Tomcat.java:235) java.lang.Exception at org.apache.tomcat.core.ContextManager.getHome(ContextManager.java:224 ) at org.apache.tomcat.core.ContextManager.getAbsolute(ContextManager.java :1512) at org.apache.tomcat.context.LoaderInterceptor.contextInit(LoaderInterce ptor.java:116) at org.apache.tomcat.core.ContextManager.initContext(ContextManager.java :491) at org.apache.tomcat.core.ContextManager.init(ContextManager.java:453) at org.apache.tomcat.startup.Tomcat.execute(Tomcat.java:195) at org.apache.tomcat.startup.Tomcat.main(Tomcat.java:235) java.lang.Exception at org.apache.tomcat.core.ContextManager.getHome(ContextManager.java:224 ) at org.apache.tomcat.task.ApacheConfig.execute(ApacheConfig.java:92) at org.apache.tomcat.startup.Tomcat.generateServerConfig(Tomcat.java:217 ) at org.apache.tomcat.startup.Tomcat.execute(Tomcat.java:200) at org.apache.tomcat.startup.Tomcat.main(Tomcat.java:235) java.lang.Exception at org.apache.tomcat.core.ContextManager.getHome(ContextManager.java:224 ) at org.apache.tomcat.task.IISConfig.execute(IISConfig.java:87) at org.apache.tomcat.startup.Tomcat.generateServerConfig(Tomcat.java:223 ) at org.apache.tomcat.startup.Tomcat.execute(Tomcat.java:200) at org.apache.tomcat.startup.Tomcat.main(Tomcat.java:235) java.lang.Exception at org.apache.tomcat.core.ContextManager.getHome(ContextManager.java:224 ) at org.apache.tomcat.task.NSConfig.execute(NSConfig.java:86) at org.apache.tomcat.startup.Tomcat.generateServerConfig(Tomcat.java:229 ) at org.apache.tomcat.startup.Tomcat.execute(Tomcat.java:200) at org.apache.tomcat.startup.Tomcat.main(Tomcat.java:235)
Re: Remove DNS lookup
Thursday, July 05, 2001, 11:35:55 PM, [EMAIL PROTECTED] wrote: DW Is there a class that can do a reverse DNS lookup, giving me the hostname DW that matches a given IP address? I'm able to retrieve the IP address of an DW HTTP request just fine using request.getRemoteAddr() (and getRemoteHost() DW returns the same IP address dotted numbers), but the java.net package DW doesn't seem to have DW anything that returns a name based on an IP address, unless I'm just DW misreading InetAddress... InetAddress.getByName(ip address).getHostName() will do what you want, if the info is available. getRemoteHost() doesn't work if the webserver is configured not to spend time doing the lookup for every request, or if no rDNS record exists for that IP. DW David
can't find tomcat.jar ?
A fresh install of 3.3-m4 (with jdk1.4 on '98), and when I try to access a jsp I get an error on finding C:\tomcat\lib\tomcat.jar. And C:\tomcat\lib\tomcat.jar does exist. Thanks for any help. org.apache.jasper.JasperException: Unable to compile Found 2 system errors: *** Error: Could not find package named: C:\tomcat\lib\tomcat.jar(java/util), C:\tomcat\work\DEFAULT\security/java/util, C:\tomcat\lib\common\jasper34_runtime.jar(java/util), C:\tomcat\lib\common\jasper-runtime.jar(java/util), C:\tomcat\lib\common\core_util.jar(java/util), C:\tomcat\lib\common\connector_util.jar(java/util), C:\tomcat\lib\common\servlet.jar(java/util) or C:\tomcat\lib\common\tomcat_core.jar(java/util) *** Error: Could not find package named: C:\tomcat\lib\tomcat.jar(java/lang), C:\tomcat\work\DEFAULT\security/java/lang, C:\tomcat\lib\common\jasper34_runtime.jar(java/lang), C:\tomcat\lib\common\jasper-runtime.jar(java/lang), C:\tomcat\lib\common\core_util.jar(java/lang), C:\tomcat\lib\common\connector_util.jar(java/lang), C:\tomcat\lib\common\servlet.jar(java/lang) or C:\tomcat\lib\common\tomcat_core.jar(java/lang)
Re[2]: Does Tomcat needs jdk 1.2.2
Tuesday, July 03, 2001, 9:35:59 AM, [EMAIL PROTECTED] wrote: EBN Thanks Randy, EBN Can you please direct me to the place were SUN says that tools.jar may not EBN be redistribute? Sun only lets you distribute the JRE. You couldn't distribute the jdk if you wanted to. Note: you might be able to distribute the jikes compiler. EBN (We are using JSPs. ) EBN Regards, EBN Eitan -Original Message- From: Randy Layman [mailto:[EMAIL PROTECTED]] Sent: Tuesday, July 03, 2001 1:33 PM To: [EMAIL PROTECTED] Subject: RE: Does Tomcat needs jdk 1.2.2 If you are using just servlets, you don't need a JDK. If you are deploying JSPs then you need the JavaC compiler (in the tools.jar file in the later versions of the JDK), which is the component that Sun indicates that you are not supposed to redistribute. Randy -Original Message- From: Eitan Ben Noach [mailto:[EMAIL PROTECTED]] Sent: Tuesday, July 03, 2001 8:49 AM To: '[EMAIL PROTECTED]' Subject: RE: Does Tomcat needs jdk 1.2.2 Thanks Sam, Actually, my intention was to ask if Tomcat need JDK at all. Now it's clear that the answer is yes. I want to be more precise: what parts of the JDK are needed, since we want to deploy Tomcat with our product, without the need of full JDK installation - only those special resources. What are they? Thanks, Eitan -Original Message- From: Sam Newman [mailto:[EMAIL PROTECTED]] Sent: Tuesday, July 03, 2001 12:36 PM To: [EMAIL PROTECTED] Subject: Re: Does Tomcat needs jdk 1.2.2 erm, my understanding is that Tomcat only requires Java 1.1.7 or above. By default the server.xml that ships with Tomcat actually comments out those areas of code that require Java 1.2/Java 2, e.g. the use of a security manager/policies sam - Original Message - From: Frans Thamura [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, July 03, 2001 11:09 PM Subject: Re: Does Tomcat needs jdk 1.2.2 Ya, JSDK. Because Tomcat is a server based on Java Frans - Original Message - From: Eitan Ben Noach [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, July 03, 2001 1:40 AM Subject: Does Tomcat needs jdk 1.2.2 Hello, Does Tomcat needs the installation of JDK 1.2.2? If yes, what specific jars ( or any other resources ) are needed? Thanks, Eitan snip
