Difference between revisions of "FAQ"

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(FAQ Sections: add FAQ about crypto changes and admin login)
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* [http://www.ecs.csus.edu/pc2/doc/faq/index.html#HELP Getting Help]
 
* [http://www.ecs.csus.edu/pc2/doc/faq/index.html#HELP Getting Help]
  
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=Unable to login as admin using Java 1.8=
 +
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This problem has been found only with Java 1.8.0_161 and pc2 version
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9.5.2 and earlier.  There is a work around below.
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 +
The symptoms are as follows:
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# The server startup seems to work
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# When logging in the Admin is stuck with a busy (hourglass) cursor
 +
# In the pc2 server log file there will be a an error (see below)
 +
 +
Java 1.8.0_161 and later have changed encryption and that causes
 +
a login problem and more.  Since pc2 encrypts both network communications
 +
and files - both areas are affected.
 +
 +
==Workaround==
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To work around this problem one must specify true for a system property <tt>jdk.crypto.KeyAgreement.legacyKDF</tt>.
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So in each pc2 script, ex pc2server or pc2admin one must add the java system property
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-Djdk.crypto.KeyAgreement.legacyKDF=true
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just after the javaw command, thus
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javaw -Djdk.crypto.KeyAgreement.legacyKDF=true
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 +
In the pc2 server log there will be an error message
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java.security.NoSuchAlgorithmException: Unsupported secret key algorithm: DES
 +
 +
==Future fix==
 +
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The pc2 development team is working on a fix for this problem.  An announcement
 +
will be sent to the pc2 announcements mail list.
  
 
== See Also ==
 
== See Also ==

Revision as of 20:32, 16 January 2018

Frequently Asked Questions (FAQ) are maintained on the PC² web site.

If you are troubleshooting or trying to get PC² to work, read the Troubleshooting section.

Click here to view FAQ.

FAQ Sections

Unable to login as admin using Java 1.8

This problem has been found only with Java 1.8.0_161 and pc2 version 9.5.2 and earlier. There is a work around below.

The symptoms are as follows:

  1. The server startup seems to work
  2. When logging in the Admin is stuck with a busy (hourglass) cursor
  3. In the pc2 server log file there will be a an error (see below)

Java 1.8.0_161 and later have changed encryption and that causes a login problem and more. Since pc2 encrypts both network communications and files - both areas are affected.

Workaround

To work around this problem one must specify true for a system property jdk.crypto.KeyAgreement.legacyKDF. So in each pc2 script, ex pc2server or pc2admin one must add the java system property

-Djdk.crypto.KeyAgreement.legacyKDF=true 

just after the javaw command, thus

javaw -Djdk.crypto.KeyAgreement.legacyKDF=true 

In the pc2 server log there will be an error message

java.security.NoSuchAlgorithmException: Unsupported secret key algorithm: DES

Future fix

The pc2 development team is working on a fix for this problem. An announcement will be sent to the pc2 announcements mail list.

See Also

External Links