It is a Division Service Support Base, not a frontline fighting unit. Basically to provide support and service to 6th Division and units under their command.
Sure or not? I knew all the "DS" units under DISCOM stood for "Direct Support" so, for a moment there, I thought there's been a name change. But your designation isn't correct too, leh, cuz DSSB is combat support & not service support.
DSSB should still stand for Direct Support Supply Bn; their sister units are DSMB (Direct Support Maintenance Bn) & DS Med Bn (Direct Support Medical Battalion). Each combat DIV has one of these outfits, commanded by an internal DISCOM (Division Support Command), but operationally they're more often deployed as smaller elements or detachments during BDE-level Exs (in rear staging areas). DSSB itself shall be in charge of things like petrol, ammo, food/water & other such stores, when out in the field.
It's a rear unit, but not rear-rear. Second-line soldiers, to be precise, athough as a formation they style themselves more as Army Logisticians than as combatants. Put it this way, their troops will still move out in helmet & rifle.
I do know Sembawang Camp is supposedly known more as Home of the Logisticians, & to a lesser extent Kranji Camp too. But no idea whetehr 6 DSSB is housed at either place.