For EL6, the glideinwms frontend has an init script for a cronjob to renew the glidein proxies (https://github.com/glideinWMS/glideinwms/blob/master/creation/templates/gwms-renew-proxies.init).
The script does not have chkconfig lines, so it can't be enabled to run on startup; this means that if the machine reboots, the cron job will be disabled, and proxies won't get renewed.
Add the necessary chkconfig lines (example here: https://github.com/opensciencegrid/rsv/blob/master/rsv-core/init/rsv.init#L3-L4).
You can test this by installing the frontend and running "chkconfig gwms-renew-proxies --on".
Once this is done, update the instructions at https://opensciencegrid.org/docs/other/install-gwms-frontend/ to tell people to run "chkconfig gwms-renew-proxies --on".
This only needs to be done for EL6, however it should be done for both glideinwms 3.4 (trunk) and 3.5 (upcoming). Once tested, send the fix upstream to the glideinwms developers.