Update :
Vtiger.com is currently facing distributed denial-of-service (DDoS), starting at 5 AM GMT (Nov 7th). These attacks either delay or prevent requests going to and from the vtiger.com, causing direct disruption to our website users. We have activated the backup page - https://cvtlogin1.vtiger.com/login/ . Please use this to continue to access your CRM.
Our Security Operations team has implemented DDOS mitigation techniques like rate limiting, limiting the no. of connections, and IP blacklisting to mitigate the risk and to regain the control. We'll post updates.
The issue was resolved.