H1B, H4 Visa

I had an appointment on 15th & 16th May 2017.
Day 1:
Went to VAC. Entrance is at the back of the main road (13.053448, 80.243130)
You can go 30 minutes before. There were 3 queues, People who had interview in the next 15-30 minutes were sent to the 1st queue. Others who arrived early were sent to the other two queues. I went 1 hour early, so i was sent to the 3rd queue. They'll give priority to the 1st queue and send inside. After a while the 1st queue became empty so some of us were sent in.
Mobiles are allowed at the VAC (not in the consulate office). They'll ask you to switch off, put it in a tray & scan it. You'll also be scanned & let in.
In my case, I had applied the DS 160 twice. I paid fees with the first one & i again filled a different form. So my visa application number and appointment confirmation numbers were different. In such a case, you'll have to mention when you meet the verifier. He'll use the latest number while he puts a bar code behind your passport. Then i waited, my token was called, he asked my name, date of birth & address for confirmation and then my fingerprints & photo were taken. That's all for day 1. I left with a seal on the application & a bar code on the back of your passport. I left at 9.45 (My appointment was at that time)

Day 2 at US consulate office:
Note on mobiles: Mobiles are strictly not allowed inside. You'll be asked in the first queue. I've read about some facility where they keep mobiles for a small fee, but i did not see any - it might have been around. My hotel receptionist assured me that the room key will not be given to any workers & i can leave my mobile at the room. So i left it there. Suggest you leave it at the hotel if there's a locker facility or on their assurance. Its better.
Went to the consulate office. There was a single long queue, no multiple time based queues like in the VAC. But time is not important, you can get on the queue, i think they'll allow even if you're late. I went 1 hour early. We were sent to one queue after another, and then another queue inside the building, big relief as there was an AC inside. By that time, my whole shirt was soaked in sweat. That queue took some time where they verified the passport once again and sent me in where interviews were being done.
There were many windows where they were conducting interviews. We were directed to those windows from a queue. When my turn came, a guy stopped me & sent the ones before me to some interviewers and did it again. I got a bit nervous, but then he sent me to one window (keep your passport & I-129 on top at this point) There was one guy being interviewed, i stood few meters behind, on a black line. That guy got rejected, the VO sent him off saying something like 'entry to US has been denied this time for you, thank you'. At that point, i became very nervous, was about to step forward, the VO signaled and told 'Sir, you'll have to wait'. VO was looking something at the computer, drank some water and called me.

Before i could say good morning, VO told please give me your passport. Rest of the conversation below - forgot the exact order
VO: Which company do you work for?
Me: xxx (my indian company)
VO: How long have you been working for them?
Me: x years
VO: What's your highest educational qualification?
Me: Engineering degree in computer science
VO: Where are you going?
Me: (paused for a second, was nervous) xxx
VO: You'll have to speak louder, i can't hear; I repeated
VO: Who's your client?
Me: xxx
VO: Sir, i can't hear, you'll have to speak - the mic is there; Then i noticed the mic & repeated, spelled it out as well; VO stared at me for a second, i got even more nervous
VO: What's your designation there?
Me: xxx (As mentioned in the petition/lca)
VO: What's you annual salary?
Me: xxx (As mentioned)
VO: Took a look at the computer to the left for a few seconds, i thought i was about to be rejected. VO told without even looking at me 'your visa is approved, thank you'.

I told 'Thank you' but VO didn't even listen i think, had turned around at that time. I left, once again finishing everything by the time of my appointment

I think there are very few rejections for H1B visas. I noticed a lot of questions being asked for others, especially students - they were taking a long time with a ton of questions.

Another quick note about Port of Entry interviews: I heard one of my known contacts got rejected and sent back. It'll be disastrous if it happens. Documents & papers are very important. They'll reject if anything is missed, stick to the role which you'll be going for (Business visa / work visa). Never deviate from mentioning those kind of work only or they'll reject. If its work visa, you'll also have to maintain the impression that client cant find / have other workers who're capable of doing it. Put your related experience or anything you have to your advantage.