@@ -60,15 +60,6 @@ void DataBlock::InitFromGrid(Grid &grid, Input &input) {
     xend[dir] = gridHost.xr[dir](gend[dir]-1);
   }
 
-  if(idfx::psize>1) {
-    idfx::cout << "DataBlock::InitFromGrid: local size is " << std::endl;
-
-    for(int dir = 0 ; dir < DIMENSIONS ; dir++) {
-      idfx::cout << "\t Direction X" << (dir+1) << ": " << xbeg[dir] << "...." << np_int[dir]
-        << "...." << xend[dir] << std::endl;
-    }
-  }
-
   // Allocate the required fields
   for(int dir = 0 ; dir < 3 ; dir++) {
     x[dir] = IdefixArray1D<real>("DataBlock_x",np_tot[dir]);
@@ -146,3 +137,17 @@ void DataBlock::ResetStage() {
 void DataBlock::SetBoundaries() {
   hydro.boundary.SetBoundaries(t);
 }
+
+void DataBlock::ShowConfig() {
+  if(idfx::psize>1) {
+    idfx::cout << "DataBlock: this process grid size is " << std::endl;
+
+    for(int dir = 0 ; dir < DIMENSIONS ; dir++) {
+      idfx::cout << "\t Direction X" << (dir+1) << ": " << xbeg[dir] << "...." << np_int[dir]
+        << "...." << xend[dir] << std::endl;
+    }
+  }
+  hydro.ShowConfig();
+  if(haveFargo) fargo.ShowConfig();
+  if(haveGravity) gravity.ShowConfig();
+}
@@ -76,7 +76,7 @@ class DataBlock {
 
   void EvolveStage();             ///< Evolve this DataBlock by dt
   void SetBoundaries();       ///< Enforce boundary conditions to this datablock
-
+  void ShowConfig();              ///< Show the datablock's configuration
 
   void ResetStage();              ///< Reset the variables needed at each major integration Stage
 
 
@@ -23,9 +23,11 @@ class DataBlockHost {
   IdefixArray3D<real>::HostMirror A[3];   // cell right interface area
 
   IdefixArray4D<real>::HostMirror Vc;     // Main cell-centered primitive variables index
+  #if MHD == YES
   IdefixArray4D<real>::HostMirror Vs;     // Main face-centered primitive variables index
   IdefixArray4D<real>::HostMirror Ve;     // Main edge-centered primitive variables index
   IdefixArray4D<real>::HostMirror J;      // Current (only when haveCurrent is enabled)
+  #endif
   IdefixArray4D<real>::HostMirror Uc;     // Main cell-centered conservative variables
   IdefixArray3D<real>::HostMirror InvDt;
 
 
@@ -242,10 +242,19 @@ void Fargo::Init(Input &input, DataBlock *data) {
     }
   #endif
 
+  
+  idfx::popRegion();
+}
+
+void Fargo::ShowConfig() {
+  idfx::pushRegion("Fargo::ShowConfig");
   if(type==userdef) {
-    idfx::cout << "Fargo: Enabled with user-defined velocity function" << std::endl;
+    idfx::cout << "Fargo: ENABLED with user-defined velocity function." << std::endl;
+    if(!fargoVelocityFunc) {
+      IDEFIX_ERROR("No Fargo velocity function has been enabled.");
+    }
   } else if(type==shearingbox) {
-    idfx::cout << "Fargo: Enabled with shearing-box velocity function" << std::endl;
+    idfx::cout << "Fargo: ENABLED with shearing-box velocity function." << std::endl;
   } else {
     IDEFIX_ERROR("Something went wrong during Fargo initialisation");
   }
@@ -267,7 +276,6 @@ void Fargo::EnrollVelocity(FargoVelocityFunc myFunc) {
                  "to be set to userdef in .ini file");
   }
   this->fargoVelocityFunc = myFunc;
-  idfx::cout << "Fargo: User-defined velocity function has been enrolled." << std::endl;
 }
 
 // This function fetches Fargo velocity when required
 
@@ -26,6 +26,7 @@ class Fargo {
   void EnrollVelocity(FargoVelocityFunc);
   void StoreToScratch();
   void CheckMaxDisplacement();
+  void ShowConfig();
 
  private:
   friend class Hydro;
 
@@ -77,12 +77,6 @@ void popRegion() {
 
 // Init the iostream with defined rank
 void IdefixOutStream::init(int rank) {
-  std::stringstream sslogFileName;
-  sslogFileName << "idefix." << rank << ".log";
-
-  std::string logFileName(sslogFileName.str());
-  this->my_fstream.open(logFileName.c_str());
-
   if(rank==0)
     this->toscreen=true;
   else
@@ -91,10 +85,14 @@ void IdefixOutStream::init(int rank) {
 
 
 // disable the log file
-void IdefixOutStream::disableLogFile() {
-  my_fstream << "Log files have been disabled (e.g. using -nowrite)." << std::endl;
-  my_fstream.close();
-  this->logFileEnabled = false;
+void IdefixOutStream::enableLogFile() {
+  std::stringstream sslogFileName;
+  sslogFileName << "idefix." << idfx::prank << ".log";
+
+  std::string logFileName(sslogFileName.str());
+  this->my_fstream.open(logFileName.c_str());
+
+  this->logFileEnabled = true;
 }
 
 } // namespace idfx
@@ -46,7 +46,7 @@ IdefixArray1D<T> ConvertVectorToIdefixArray(std::vector<T> &inputVector) {
 class idfx::IdefixOutStream {
  public:
   void init(int);
-  void disableLogFile();
+  void enableLogFile();
   // for regular output of variables and stuff
   template<typename T> IdefixOutStream& operator<<(const T& something) {
     if(toscreen) std::cout << something;
@@ -63,7 +63,7 @@ class idfx::IdefixOutStream {
  private:
   std::ofstream my_fstream;
   bool toscreen;
-  bool logFileEnabled{true};   //< whether streams are also written to a log file
+  bool logFileEnabled{false};   //< whether streams are also written to a log file
 };
 
 class idfx::IdefixErrStream {
 
@@ -22,15 +22,11 @@ void Gravity::Init(Input &input, DataBlock *datain) {
       std::string potentialString = input.Get<std::string>("Gravity","potential",i);
       if(potentialString.compare("userdef") == 0) {
         this->haveUserDefPotential = true;
-        idfx::cout << "Gravity: Enabling user-defined gravitational potential" << std::endl;
       } else if (potentialString.compare("central") == 0) {
         this->haveCentralMassPotential = true;
         this->centralMass = input.GetOrSet<real>("Gravity","Mcentral",0, 1.0);
-        idfx::cout << "Gravity: Enabling central mass gravitational potential with M="
-                   << this->centralMass << std::endl;
       } else if (potentialString.compare("selfgravity") == 0) {
         this->haveSelfGravityPotential = true;
-        idfx::cout << "Gravity: Enabling self Gravity" << std::endl;
       } else {
         IDEFIX_ERROR("Unknown type of gravitational potential in idefix.ini. ");
       }
@@ -42,7 +38,6 @@ void Gravity::Init(Input &input, DataBlock *datain) {
     std::string potentialString = input.Get<std::string>("Gravity","bodyForce",0);
     if(potentialString.compare("userdef") == 0) {
       this->haveBodyForce = true;
-      idfx::cout << "Gravity:: Enabling user-defined body force" << std::endl;
     } else {
       IDEFIX_ERROR("Unknown type of body force in idefix.ini. "
                    "Only userdef is implemented");
@@ -62,6 +57,31 @@ void Gravity::Init(Input &input, DataBlock *datain) {
   }
 }
 
+void Gravity::ShowConfig() {
+  if(data->haveGravity) {
+    idfx::cout << "Gravity: ENABLED." << std::endl;
+    if(haveUserDefPotential) {
+      idfx::cout << "Gravity: User-defined gravitational potential ENABLED." << std::endl;
+      if(!gravPotentialFunc) {
+        IDEFIX_ERROR("No user-defined gravitational potential has been enrolled.");
+      }
+    }
+    if(haveCentralMassPotential) {
+      idfx::cout << "Gravity: central mass gravitational potential ENABLED with M="
+                  << this->centralMass << std::endl;
+    }
+    if(haveSelfGravityPotential) {
+      idfx::cout << "Gravity: self-gravity ENABLED." << std::endl;
+    }
+    if(haveBodyForce) {
+      idfx::cout << "Gravity: user-defined body force ENABLED." << std::endl;
+      if(!bodyForceFunc) {
+        IDEFIX_ERROR("No user-defined body force has been enrolled.");
+      }
+    }
+    
+  }
+}
 // This function compute the gravitational field, using both body force and potential
 void Gravity::ComputeGravity() {
   idfx::pushRegion("Gravity::ComputeGravity");
@@ -107,7 +127,6 @@ void Gravity::EnrollPotential(GravPotentialFunc myFunc) {
                  "with the potential entry in [Gravity].");
   }
   this->gravPotentialFunc = myFunc;
-  idfx::cout << "Gravity: User-defined gravitational potential has been enrolled" << std::endl;
 }
 
 void Gravity::EnrollBodyForce(BodyForceFunc myFunc) {
@@ -117,7 +136,6 @@ void Gravity::EnrollBodyForce(BodyForceFunc myFunc) {
                  "with the bodyForce entry in [Gravity].");
   }
   this->bodyForceFunc = myFunc;
-  idfx::cout << "Gravity: User-defined body force function has been enrolled" << std::endl;
 }
 
 // Fill the gravitational potential with zeros
 
@@ -35,6 +35,7 @@ class Gravity {
 
   void AddCentralMassPotential();   ///< Àdd the potential due to a centrall mass
 
+  void ShowConfig();                ///< Show the gravity configuration
   bool havePotential{false};        ///< Whether a gravitational potential is present
                                         ///< in which case, (at least) one of the following is true
   bool haveUserDefPotential{false};     ///< Whether a potential is defined by user
 
@@ -18,8 +18,6 @@ Grid::Grid() {
 Grid::Grid(Input &input) {
   idfx::pushRegion("Grid::Grid(Input)");
 
-  idfx::cout << "Grid: allocating Grid." << std::endl;
-
   // Get grid size from input file, block [Grid]
   int npoints[3];
   for(int dir = 0 ; dir < 3 ; dir++) {
@@ -257,3 +255,64 @@ Grid& Grid::operator=(const Grid& grid) {
     return *this;
 }
 */
+
+void Grid::ShowConfig() {
+  for(int dir = 0 ; dir < DIMENSIONS ; dir++) {
+    idfx::cout << "Grid: ";
+    std::string lboundString, rboundString;
+      switch(lbound[dir]) {
+        case outflow:
+          lboundString="outflow";
+          break;
+        case reflective:
+          lboundString="reflective";
+          break;
+        case periodic:
+          lboundString="periodic";
+          break;
+        case internal:
+          lboundString="internal";
+          break;
+        case shearingbox:
+          lboundString="shearingbox";
+          break;
+        case axis:
+          lboundString="axis";
+          break;
+        case userdef:
+          lboundString="userdef";
+          break;
+        default:
+          lboundString="unknown";
+      }
+      switch(rbound[dir]) {
+        case outflow:
+          rboundString="outflow";
+          break;
+        case reflective:
+          rboundString="reflective";
+          break;
+        case periodic:
+          rboundString="periodic";
+          break;
+        case internal:
+          rboundString="internal";
+          break;
+        case shearingbox:
+          rboundString="shearingbox";
+          break;
+        case axis:
+          rboundString="axis";
+          break;
+        case userdef:
+          rboundString="userdef";
+          break;
+        default:
+          rboundString="unknown";
+      }
+
+      idfx::cout << "Direction X" << (dir+1) << ": " << lboundString << "\t" << xbeg[dir]
+                 << "...." << np_int[dir] << "...." << xend[dir] << "\t" << rboundString
+                 << std::endl;
+  }
+}