# Building ACCESS-OM2 on Archer2 (UK HPC) **URL:** \ **Category:** spack\ **Tags:** spack, access-om2\ **Created:** [5 February 2026 12:44 UTC](https://forum.access-hive.org.au/t/building-access-om2-on-archer2-uk-hpc/5872 "2026-02-05T12:44:55Z")\ **Posts on this page:** 1\ **Showing post:** 13
**Author:** ![davemunday](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/davemunday/32/3688_2.png) [@davemunday](https://forum.access-hive.org.au/u/davemunday)\ **Post date:** [9 February 2026 17:51 UTC](https://forum.access-hive.org.au/t/building-access-om2-on-archer2-uk-hpc/5872/13 "2026-02-09T17:51:36Z")
More by way of documenting somewhere what I’ve been doing, I thought I’d continue to update, despite not really getting anywhere! Following the advice here: [Debug Spack "Error: failed to concretize"](https://forum.access-hive.org.au/t/debug-spack-error-failed-to-concretize/5878), I’ve looked into the concretize error by trying individual components. Consistently I get issues with `netcdf-fortran` and `netcdf-c`. ```auto [ACCESS-OM2] munday@archer2 >> spack solve cice5 ==> Error: failed to concretize `cice5` for the following reasons: 1. cannot satisfy a requirement for package 'netcdf-fortran'. 2. cannot satisfy a requirement for package 'netcdf-c'. ``` To try and obtain more information, I deactivated the spack env and tried to install netcdf-fortran. This causes a conflict with an external module: ```auto munday@archer2 >> spack install netcdf-fortran ==> netcdf-fortran@4.9.0.7 : has external module in ['cray-hdf5-parallel/1.12.2.7', 'cray-netcdf-hdf5parallel'] [+] /opt/cray/pe/netcdf-hdf5parallel/4.9.0.7/gnu/9.1 (external netcdf-fortran-4.9.0.7-5ls7gh4entsmweu3fuk577s5ystzn5wt) ``` A curious thing here is that I didn’t have the `cray-hd5-parallel` or `cray-netcdf-hdf5parallel` modules loaded. I use `MITgcm` the most and so my default modules are the ones I use for its compilation: `cray-netcdf/4.9.0.7` and `cray-hdf5/1.12.2.7`. ```auto munday@archer2 >> module list Currently Loaded Modules: 1) craype-x86-rome 5) xpmem/0.2.119-1.3_0_gnoinfo 9) cray-mpich/8.1.27 13) epcc-setup-env 17) cray-python/3.10.10 21) spack/1.0.2 2) libfabric/1.12.1.2.2.0.0 6) cce/16.0.1 10) cray-libsci/23.09.1.1 14) load-epcc-module 18) nco/5.1.6 3) craype-network-ofi 7) craype/2.7.23 11) PrgEnv-cray/8.4.0 15) cray-hdf5/1.12.2.7 19) ncview/2.1.11 4) perftools-base/23.09.0 8) cray-dsmml/0.2.2 12) bolt/0.8 16) cray-netcdf/4.9.0.7 20) other-software/1.0 ``` If I try to install a specific `netcdf-fortran` or `netcdf-c` version I get a much longer error message: ```auto munday@archer2 >> spack install netcdf-fortran@=4.6.2 ==> Error: failed to concretize `netcdf-fortran@=4.6.2` for the following reasons: 1. Cannot satisfy 'netcdf-fortran@=4.6.2' required because netcdf-fortran@=4.6.2 requested explicitly 2. Cannot satisfy 'netcdf-fortran@=4.6.2' 3. Cannot satisfy 'netcdf-fortran@=4.9.0.7' and 'netcdf-fortran@=4.6.2 required because netcdf-fortran available as external when satisfying netcdf-fortran@=4.9.0.7 %aocc required because netcdf-fortran available as external when satisfying netcdf-fortran@=4.9.0.7 %gcc required because netcdf-fortran available as external when satisfying netcdf-fortran@=4.9.0.7 %cce required because netcdf-fortran@=4.6.2 requested explicitly required because netcdf-fortran@=4.6.2 requested explicitly required because netcdf-fortran available as external when satisfying netcdf-fortran@=4.9.0.7 %cce required because netcdf-fortran@=4.6.2 requested explicitly required because netcdf-fortran@=4.6.2 requested explicitly 4. Cannot satisfy 'netcdf-fortran@=4.9.0.7' and 'netcdf-fortran@=4.6.2 required because netcdf-fortran available as external when satisfying netcdf-fortran@=4.9.0.7 %cce required because netcdf-fortran available as external when satisfying netcdf-fortran@=4.9.0.7 %gcc required because netcdf-fortran available as external when satisfying netcdf-fortran@=4.9.0.7 %aocc required because netcdf-fortran@=4.6.2 requested explicitly required because netcdf-fortran@=4.6.2 requested explicitly required because netcdf-fortran available as external when satisfying netcdf-fortran@=4.9.0.7 %aocc required because netcdf-fortran@=4.6.2 requested explicitly required because netcdf-fortran@=4.6.2 requested explicitly 5. Cannot satisfy 'netcdf-fortran@=4.9.0.7' and 'netcdf-fortran@=4.6.2 required because netcdf-fortran@=4.6.2 requested explicitly required because netcdf-fortran available as external when satisfying netcdf-fortran@=4.9.0.7 %gcc required because netcdf-fortran available as external when satisfying netcdf-fortran@=4.9.0.7 %cce required because netcdf-fortran available as external when satisfying netcdf-fortran@=4.9.0.7 %aocc required because netcdf-fortran@=4.6.2 requested explicitly required because netcdf-fortran@=4.6.2 requested explicitly required because netcdf-fortran available as external when satisfying netcdf-fortran@=4.9.0.7 %aocc required because netcdf-fortran@=4.6.2 requested explicitly ``` It doesn’t matter whether the `cray-netcdf` module is loaded, or not. --- _[View the full topic](https://forum.access-hive.org.au/t/building-access-om2-on-archer2-uk-hpc/5872)._