How do I detect a slow link / set slow link threshold?

i have 650 pos windows xp machines accessible via vpn connection our data center.  these machines scheduled reboot via scheduled task nightly between 2 , 3 - there 3 different times within hour of these machines reboot.  so - when reboot occurs theoretically, there 200+ machines rebooting @ once.  

we seeing hit , miss issues of extremely long logins occurring (5-10-15+ min). have enabled verbose logging login process - , seeing machines hanging on "applying group policy" or "applying schedule tasks" or "login scripts".

my thought - gpo on vpn may impact performance, , in addition, have 230 machines trying pull down gpo settings @ same time - may cause enough network congestion cause slow link.

so question - how can determine if gpo detecting slow link?  if need adjust default of 500kbps, how determine adjust number to?  i realize simple solution may further stagger reboot process, however, have hour window type of maintenace because of our hours of business / other automated processes occur during night.

thanks in advance replies!

sb

hi sb,

1. can adjust slow link settings here: computer config\admin templates\system\group policy - configure group policy slow link detection. test, might want bump min link up.

2. if have windows vista+ client accessing it, can take advantage of gp event log - see event records connection speed.

3. may want consider limiting run time of each of client side extensions well. example, set computer config\admin templates\system\scripts - specify max wait time gp scripts lower value default 10 minutes. ensure aren't mixing problems (a slow script slow link).

Windows Server  >  Group Policy