• Monitor of type "STOREFRONT" on NetScaler fails intermittently. 

• This results in StoreFront services flapping on NetScaler. 

• The StoreFront services are added for secure connection i.e. port 443.

• This issue is observed both in NetScaler 10.5 and 11.0 firmware.

• The event logs on the NetScaler showed the following messages:
  1011788       0           2445          1        0 mon_tot_failed MonServiceBinding_x.x.x.x:443_(lb_mon_stg)(lb_svc_sf_a) Thu Apr 23 19:24:37 2015 (Aggr)
  1011789       0           2393          1        0 mon_tot_failed_code MonServiceBinding_x.x.x.x:443_(lb_mon_stg)(lb_svc_sf_a) Thu Apr 23 19:24:37 2015 (Aggr)
  
  40014   141 PPE-0 MonServiceBinding_x.x.x.x:443_(lb_mon_thin)(lb_svc_sf_a): DOWN; Last response: Failure - Probe failed. Thu Apr 23 20:50:17 2015
  40022    29 PPE-0 MonServiceBinding_x.x.x.x:443_(lb_mon_thin)(lb_svc_sf_a): UP; Last response: Success - Probe succeeded. Thu Apr 23 20:50:47 2015

This is caused by an issue with an existing Perl (script) module that does not calculate the time accurately resulting in the incorrect reporting of timeout.

This issue has been fixed in the following firmware versions:

• 10.5.60.7nc
• 11.0.64.34nc

Workaround: If your deployment allows non-secure connections, use a non-secure StoreFront monitor.