Dear R-users, I am trying to make Snow and Rmpi working on an heterogenous cluster of linux computers. The master computer is built on a 64 bit architecture whereas all nodes are built on a 32 bit architecture. LAM/MPI was installed successfully on all machine. LAM boots correctly on the master computer and it recognizes all nodes defined in the lamhosts file. However, when starting R, launching the 'snow' package and making a cluster including several nodes, everything is blocked. It seems that Rmpi cannot be started in the nodes which have a different architecture. I have to do 'lamhalt' on the first node of the cluster so that R is stopped on the master computer. On the other hand, using 'snow' and 'Rmpi' on an homogeneous cluster works pretty fine. I read on the 'snow' documentation that for non-homogeneous clusters of computers different settings are needed. On the master computer and on each nodes, I copied the script RunSnowNode to the /usr/local/bin directory and defined the R_SNOW_LIB and R_HOME_LIB variables in /etc/profile as follow: R_SNOW_LIB="/usr/local/lib64/R/library" export R_SNOW_LIB R_HOME_LIB="/usr/local/lib64/R/library" export R_HOME_LIB for the 64 bit architecture and: R_SNOW_LIB="/usr/local/lib/R/library" export R_SNOW_LIB R_HOME_LIB="/usr/local/lib/R/library" export R_HOME_LIB for the 32 bit architecture. In addition the same version of R is installed on all computers (nodes + master). Nevertheless, the heterogeneous cluster is not working... Does anyone can help me solving this problem? Thanks a lot in advance. Florent -- -------------------------------------------------- Dr Florent BATY Pulmonary Gene Research, Universit??tsspital Basel Petersgraben 4, CH-4031 Basel, Switzerland tel: +41 61 265 57 27 - fax: +41 61 265 45 87