I got a rank of 3031 in JEE Mains 2016. In mock counseling I missed MNNIT CSE and got IIIT Allahabad IT.Will IIITA be as good as MNNIT?

Yes, IIIT Allahabad is also a decent institute, providing a similar graded placement as MNNIT Allahabad. There are several similarities between the two institutes, with some added advantages of being in IIIT Allahabad too. 

The table below gives a brief level of comparison among the two institutes.

Key Highlights:

• The IT department of IIIT Allahabad has a smaller batch size than CSE at MNNIT Allahabad, along with some better lab facilities in the institute.
• The placements in both institutes are more or less the same. Most companies visit both the institutes, both of the institutes being in the same city.
• The coding environment in IIIT Allahabad is much better than in MNNIT Allahabad.
• The subjects in IT at IIIT Allahabad are almost the same as the subjects in CSE, with slight differences in curriculum.
• The labs in IIIT Allahabad are excellently maintained and properly equipped with instruments.

Therefore, IIIT Allahabad is no doubt an excellent institute for IT and the candidate will be in no loss choosing the institute. Other than that, it depends upon the candidate as to how much he/she can put the effort into preparation.