c - Ruby crashing and emitting 'Illegal instruction' -

on client's legacy rails 2.1.1 app, i'm encountering error ruby crashes , emits 'illegal instruction.' crash triggered calls methods on digest::sha2.

>> digest::sha2 => digest::sha2 >> digest::sha2.new() illegal instruction 

the rails app running on 2 servers behind load balancer. stacks on 2 servers close being identical , 1 triggers crash. they're both ree 1.8.7, rails 2.1 , debian 6. 1 running linux kernel version 3.9.3 , 1 running version 3.9.2—but i'm unsure how determine if that's relevant.

digest::sha2 seems implemented in c. know little c , diagnosing 1 on head. / pointers in right direction appreciated!

thanks bunch!!

environment info

here's ree source digest::sha2: https://github.com/foobarwidget/rubyenterpriseedition187-330/tree/master/ext/digest/sha2

on server that's encountering crash:

hostname@node1:~/appname$ cat /etc/issue debian gnu/linux 6.0 \n \l  hostname@node1:~/appname$ uname -a linux node1.hostname.org 3.9.2-x86_64-[redacted] #1 smp tue may 14 17:16:34 edt 2013 x86_64 gnu/linux  hostname@node1:~/appname$ ruby /opt/ruby-enterprise-1.8.7-2012.02/bin/ruby  hostname@node1:~/appname$ irb irb(main):001:0> require 'digest' => true irb(main):002:0> digest::sha2.hexdigest('foo') => "2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae" irb(main):003:0> exit  hostname@node1:~/appname$ ./script/console loading development environment (rails 2.1.1) >> digest::sha2.hexdigest('foo') illegal instruction 

on server not crashing:

hostname@node2:~/appname$ cat /etc/issue debian gnu/linux 6.0 \n \l  hostname@node2:~/appname$ uname -a linux node2.hostname.org 3.9.3-x86_64-[redacted] #1 smp mon may 20 10:22:57 edt 2013 x86_64 gnu/linux  hostname@node2:~/appname$ ruby /opt/ruby-enterprise-1.8.7-2012.02/bin/ruby  hostname@node2:~/appname$ irb irb(main):001:0> require 'digest' => true irb(main):002:0> digest::sha2.hexdigest('foo') => "2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae" irb(main):003:0> exit  hostname@node2:~/appname$ ./script/console loading development environment (rails 2.1.1) >> digest::sha2.hexdigest('foo') => "2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae"