+# bonding
+
+Say you have
+
+* one build `2015.04.13--f14` under test
+* another build `2015.04.13--f18` that you would like to use to create f18 nodes inside `2015.04.13--f14`
+
+general idea is to use this command
+
+ root@testmaster ~/2015.04.13--f14 # run -g 2015.04.13--f18 ...
+
+or in an equivalent manner
+
+ export bonding= 2015.04.13--f18
+ run -G
+
+# requirements
+
+* the build to test (f14) must be running
+* the build to bond with does not need to run but needs to be have run under `../2015.04.13--f18` so that its arg-* files reflect its flavour
+
+# convenience
+
+* rung can be used as a symlink to `TestMain.py`
+* in this case it is like running `run -G`
+
+* plus, `comp-testmaster` offers the convenience function
+
+ bond ../$(t)*18
+
+* or, even simpler
+
+ bond18
+
+# initialisation
+
+ bond18
+ rung
+
+will define the f18 node flavour to the f14 build
+
+# creating bonding node
+
+ rung nodes
+
+will create an additional node in tested myplc.
+
+**NOTE** for efficiency the IP and hostname of that node are stored in `arg-bonding-$bonding`
+
+# starting node
+
+as a matter of fact when doing `run -g $bonding` one can invoke most of the usual targets, including for starting the node
+
+ rung start-node wait-node
+
+# usual sequence
+
+ alias rung='run -g $bonding'
+ bonding=2015.04.13--f21
+ rung
+ rung -n bonding-node
+ cat arg-bonding-$bonding
+ <<visual check>>
+ rung bonding-node
+