As Putin sees it, that resolution was taken way beyond its stated purpose of imposing a no-fly zone over Libya — it also opened the door for a full-scale military intervention. Under the U.N. mandate, the U.S. and NATO began flying bombing raids against Gaddafi’s military convoys, which were then moving toward the rebel-held city of Benghazi with the express aim of “cleansing” its revolutionary populace. After fending off that assault, NATO air power continued to provide the rebels with a clear military advantage.There won't be another "no fly zone" resolution coming out of UN Security Council regarding Syria. As I wrote before, the Libyan No Fly Zone was a full out air war against the Qaddafi at the time.
Within weeks, Gaddafi’s army was routed, his convoy was bombed from the air while fleeing the Libyan capital, and the dictator himself was captured hiding in a drain pipe in his hometown. A video of rebels beating, insulting and finally killing Gaddafi soon appeared on YouTube. Putin was furious over this turn of events — seeing it as a blatant violation of Libyan sovereignty and a betrayal of Russia’s willingness to trust the west’s intentions. He has not gotten over the slight. “What we really do not want is to allow the same mistake as with Libya,” Klimov says, “when we believed we were getting one thing and got something totally different.” Time
Russia wants Assad out but the regime to stay, possible reformed, but still within Russia's sphere of influence. They are using the US playbook on Yemen on Syria (kick the dictator, replace it with somebody within the regime, change the regime within your influence).