Now copyKernels allows both /nix/store and /boot be on separate partitions (you need to specify where /boot is for this).

svn path=/nixos/trunk/; revision=9949

installer/grub-menu-builder.sh

@@ -45,6 +45,11 @@ addEntry() {
             cp $initrd $initrd2
         fi
         initrd=$initrd2
+
+        if test -n "@bootMount@"; then
+          kernel=$(echo $kernel2 | sed -e 's^/boot^@bootMount@^')
+          initrd=$(echo $initrd2 | sed -e 's^/boot^@bootMount@^')
+        fi
     fi
     
     local confName=$(if test -e $path/configuration-name; then 

system/options.nix

@@ -53,6 +53,17 @@
       ";
     };
 
+    bootMount = mkOption {
+      default = "";
+      example = "(hd0,0)";
+      description = "
+        If the system partition may be wiped on reinstall, it is better
+        to have /boot on a small partition. To do it, we need to explain
+        to GRUB where the kernels live. Specify the partition here (in 
+        GRUB notation.
+      ";
+    };
+
     kernel = mkOption {
       default = pkgs: pkgs.kernel;
       description = "

system/system.nix

@@ -322,6 +322,7 @@ rec {
     path = [pkgs.coreutils pkgs.gnused pkgs.gnugrep];
     copyKernels = config.boot.copyKernels;
     extraGrubEntries = config.boot.extraGrubEntries;
+    bootMount = config.boot.bootMount;
   };