If while installing json module from the WHM under Software > Module Installer > PHP Pecl you get the following error.
ERROR: `phpize\’ failed
The json.so object is not in /usr/local/lib/php/extensions/no-debug-non-zts-20060
ERROR: `/root/tmp/pear/cache/json-1.2.1/configure’ failed
You can downloaded the source, do a ./configure, make, make install then copy the json.so over to the php extensions directory.
But the above error you have encountered is as the /tmp is being mounted as nonexec.
So the workaround to resolve the above issue is
1. Login to SSH
2. Make tmp and var/tmp exec
mount -v -o remount,exec /tmp
mount -v -o remount,exec /var/tmp
3. No go ahead and install JSON
pecl install json
4 . And finally, make tmp and var/tmp noexec again
mount -v -o remount,noexec /tmp
mount -v -o remount,noexec /var/tmp