This is announced in an article by international volunteer community InformNapalm, Censor.NET informs.
"The fact that Nikolay (profile, albums) is an acting military of the marines and serves in Sputnik village is evidenced by photos from his albums ( , ,  ). It's worth noting that the most recent image was uploaded on March 2, 2016," the authors of the material note.
The following group photograph captioned "Marines Sputnik" helped identifying his belonging to the 1st brigade of marines of Russia's Northern Fleet.
In summer 2014 a unit of the 61st brigade of the Northern Fleet of the Russian Federation was ordered to redeploy to Rostov Oblast for drills. (This assumption is based on InformNapalm's investigation titled "Evidence of the Participation of the 61st Marine Brigade of the Russian Navy's Northern Fleet in the Fights in Donbas," which unveils the facts proving participation of this unit in Donbas battles between summer 2014 and February 2015.) It's important that images made in 2014 were uploaded to the album in January 2016. The camp from which marines were invading Ukraine is located in Chertkov district of Rostov Oblast, in proximity to the Ukrainian border.
Here are exact coordinates of the location. The image (archive) shows Bolshakov in a machine gun emplacement with a Utes NSV. It is followed by even more interesting photo, showing Bolshakov with the same Utes on the territory of Ukraine, in Vyshnevyi Dil village of the Luhansk region in Ukraine. Pay attention to the geotag of this photo.
With GoogleEarth service it became possible to locate the exact location (here) of the photo, the machine gun's position, and the direction of pointing (marked by a yellow arrow).
Another image confirming Bolshakov's presence in the Luhansk region was made at Madrydska and Chernyshevskoho Streets in Luhansk city. The exact location is here. It's interesting to note an armored assault vehicle or a 2S9 Nona-S howitzer in the background.
Related materials: Evidence of Russian aggression in Ukraine