I need to create a rule with a dns name like www.vmware.com , is it possible to do it on a r75 or r77.30;
Yes, you can do this with domain objects.
However, Domain objects are not the preferred approach unless you're using R80.10 or later, as there are some performance implications.
Please refer to the following SK: Best Practices - Working with Domain Objects (Pre R80.10)
As Dameon said, domain objects are rather useless pre R80.10.
Have you considered using dynamic objects (Configuring Dynamic Objects)?
You will have to script or manually add IPs into gateway but it might fit your requirements.
Domain & Dynamic Objects are accelerated with R80.10 Gateways. So while it is doable with Pre-R80 Gateways, we got customers who upgraded their gateways to R80.10 for that reason alone.. ;-)
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