The most common cause of a slow login to NetStorage is large or poorly configured login scripts. When a user authenticates to the Primary Authentication domain, all applicable login scripts for that user object are processed. The more commands executed, the longer the login process.
Invalid authentication domains can also slow the login process. After the user has been authenticated to the Primary authentication domain, the same username and password is used to authenticate to any Secondary authentication domains. Authentication failure on any of these domains slows logins. Users can successfully authenticate to the Primary Authentication domain but fail at each of the secondary domains.
It is helpful to determine if slow logins are global (all users) or specific to a given user object. If all users are affected, it is more likely to be a problem with the XTier authentication domain configuration. If a single user or groups of users are affected, check all login scripts that apply to that user or group. A problem with a context’s login script can affect a large number of users. Finding out which scripts apply to which users can help narrow the problem.
For more information on how NetStorage works with login scripts, see "Login Script Processing by NetStorage" TID10068983".