How to Get There from bangalore
By Bus
There are many bus options to go to Pondicherry from Bangalore. Government services as well private bus services, luxury buses as well as less luxurious "deluxe" buses. The journey takes between seven and eight hours. The preferred buses are the ones that do an overnight journey. However, beware that tickets, especially for weekends, are pretty hard to come by. So make sure you book well in advance.
You can board most private buses either at Kalasipalya or at Madiwala. Government bus services start from the Kempe Gowda Bus Station. Most overnight buses start at around 9 or 10 PM and reach Pondicherry at around five the next morning.
Some bus services I have travelled by extensively with a reasonably good experience are Indira Travels, SRS Travels, KSRTC, and PRTC. KSRTC and PRTC both have semi-sleeper Volvo buses, which are a bit safer and a lot more comfortable than other buses. The PRTC bus leaves Bangalore at 2 PM and reaches Pondicherry at around 9:30 PM, while the KSRTC one starts at around 10 PM and reaches Pondicherry at around 5 AM. Indira and KPN, on the other hand, both offer a sleeper option.
By Road
The road to Pondicherry from Bangalore is of about 350 kms. Take the Hosur Road till Krishnagiri, take a left off the main highway (road signs show the turn) and then take National Highway 66 (NH-66) to Thiruvannamalai and then to Pondicherry. You will cross Uthangarai, Chengam, Tiruvannamalai, Gingee and Tindivanam on the way. The journey takes between five and six hours. Gingee has a fort which is a great place to take a break. Make sure you pack some food as there aren't any good places to dine on the way.