New Alcatraz (2001) on Netflix

In the middle of Antarctica, a highly maximum security prison called New Alcatraz is fully operational. When a mining crew inside the prison runs across a strange rock formation. What they don't know is that a giant, violent prehistoric snake is inside the formation. After it breaks out of the formation, the snake goes on a killing rampage inside the prison.To get help, scientists and a group of soldiers must eliminate the snake before it takes over the prison, leaving the humans on the bottom of the chain.