currently no trace flags, but i will handle this tonight and post errors here. the setup is:

two ibm x3650 M3 servers, one cpu (4 core) each, 72GB ram, 4 onboard nic, 2 10GE nics for the storage, switched via an arista 10GE fan out. storage is a netapp 3020, servers got 9 luns on the storage, one for each sysdb, db, log (x2, for both instances) plus backup, monitoring and application transfers. the crazy thing is, that the services are all up and running in each scenario but can´t get reached from nowhere. if there was a problem with storage than the sql server services wouldnt start. i think that there is a problem with either the cluster services or the sql services, maybe could be dns, also