Triumphant ( Genesis Fleet #3 ) [Campbell, Jack]

"The recently colonized world of Glenlyon has learned that they're stronger when they stand with other star systems than when they are on their own. But after helping their neighbor Kosatka against an invasion, Glenlyon has become a target. An attack is launched against Glenlyon's orbital facility with forces too powerful for fleet officer Rob Geary to counter using their sole remaining destroyer, Saber. Mele Darcy's Marines must repel repeated assaults while their hacker tries to get into the enemy systems to give Saber a fighting chance"--