Hi
I got a H1B visa and my mom is entirely dependent on me.
I can take her only through B2 which is short.
Can any one tell me how can I sustain her there as long as I hold my H1b.
Many people say that B2 extensions might work, but if failed, the entire visa will be cancelled?
If not How do I manage to extend the B2 for every 6 months? Valid reason?
Please help me with your valuable suggestions.

Thanks in advance

Those who are qualified for dependent visas are spouse and children only, parents not included.

She may not be able to extend B1/B2 more than once. Aliens can file for extension but all together must not exceed 1 year and after that the chance to get a new visa is zero.

If you want to take this job offer, hire caregiver/companion to take care of her in your home country.