Managing the JavaOS Checksum

Each time you receive a new copy of the JavaOS software, you can configure the DHCP server to deliver the new copy to JavaStation computers by following the first set of instructions below. To disable JavaOS updating on the JavaStation computers, follow the second set of instructions.

To Configure the DHCP Server for a New JavaOS Binary

1. Determine the checksum.

   The checksum is contained in the first 4 bytes of the last 12 bytes of the JavaOS binary file.

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   % tail -12c  javaos | od -X | nawk '{print "0x" $2}'
   14eb02a1 

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2. Use dhtadm to add the new checksum to the DHCP configuration.

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   % dhtadm -M -m SUNW.JSIIep -e JOSchksm=0xchecksum 
   

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For example,

% dhtadm -M -m SUNW.JSIIep -e JOSchksm=0x14eb02a1 

When each JavaStation computer boots, its flash memory is updated with the new JavaOS binary and then is rebooted using the new JavaOS binary. This action may be automatic or require user confirmation, depending on other options.

To Disable JavaOS Updating

1. Set the checksum to zero:

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   % dhtadm -M -m SUNW.JSIIep -e JOSchksm=0
   

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or

1. Delete the checksum entirely from the DHCP configuration:

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   % dhtadm -M -m SUNW.JSIIep -e JOSchksm= 
   

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Note that there is nothing after the equal sign.