The work performed by network administrators to address sudden, dynamic, heterogeneous, and time specific situations that happen in the network management domain is complex. In this paper, we introduce an approach that allows network administrators to overcome the complexity of handling these network management situations (called NMSits). The approach is made up of Mashments that are special mashups used to cope with NMSits, the process to develop and execute Mashments, and the Mashment Maker that supports such model and process. We use IT Service Management metrics to evaluate our approach, measuring the complexity of facing, with and without the Maker, a specific NMSit that occurs in several networks based on the Software Defined Networking paradigm. The evaluation results demonstrate that the complexity decreases when network administrators use our approach to handle NMSits.