ERROR: failed to write shared server hostfile

Hi.
I installed the latest develop version of unifyfs using spack.
When I try to start the unifyfs server deamon using the following command:
unifyfs start --share-dir=/home/[my user]/[some dir] &
I get the following error:
ERROR: no supported resource manager detected

I tried it both with the dedicated slurm installed while installing unifyfs and with my default slurm installation.

The command I used to install unifyfs is:
spack install unifyfs +auto-mount +fortran +hdf5 +pmi ^openmpi +cxx_exceptions fabrics=verbs +legacylaunchers +pmi schedulers=slurm +thread_multiple +vt
and am using spack@0.14.0 and the gnu@8.1.0 compiler.
Take note that I did install unifyfs with openmpi with slurm and fabrics support.

Here is the list of loaded spack packages and I used with their variants:

spack find --loaded --variants
==> 44 installed packages
-- linux-centos7-x86_64 / gcc@8.1.0 -----------------------------
argobots@1.0rc2~debug~valgrind
bmi@develop
boost@1.72.0+atomic+chrono~clanglibcpp~container~context~coroutine cxxstd=98 +date_time~debug+exception~fiber+filesystem+graph~icu+iostreams+locale+log+math~mpi+multithreaded~numpy~pic+program_options~python+random+regex+serialization+shared+signals~singlethreaded+system~taggedlayout+test+thread+timer~versionedlayout visibility=hidden +wave
bzip2@1.0.8+shared
curl@7.68.0~darwinssl~gssapi~libssh~libssh2~nghttp2
expat@2.2.9+libbsd
flatcc@0.5.3 build_type=RelWithDebInfo +shared
gdbm@1.18.1
gettext@0.20.1+bzip2+curses+git~libunistring+libxml2+tar+xz
glib@2.56.3~libmount patches=c325997b72a205ad1638bb3e3ba0e5b73e3d32ce63b2d0d3282f3e3a2ff4663c tracing=none
gotcha@0.0.2 build_type=RelWithDebInfo ~test
hdf5@1.10.6~cxx~debug~fortran~hl+mpi+pic+shared~szip~threadsafe
hwloc@1.11.11~cairo~cuda~gl+libxml2~nvml+pci+shared
json-c@0.13.1
leveldb@1.22 build_type=RelWithDebInfo +shared
libbsd@0.10.0
libfabric@1.8.1 fabrics=sockets,tcp,udp ~kdreg
libffi@3.2.1
libgcrypt@1.8.5
libgpg-error@1.36 patches=b185b1ebaea7f8ae74d58c828eb9008cff7c21431b6041aa0de072cb797c77a8
libiconv@1.16
libnl@3.3.0
libpciaccess@0.13.5
libxml2@2.9.9~python
lz4@1.9.2
margo@0.4.3+shared
mercury@1.0.1+bmi+boostsys build_type=RelWithDebInfo ~cci~mpi+ofi patches=34fc95b3599c74a8cece6e873cfdc8bc0afe2dc0deabb6e2d11ea2a93f0cebf5 +selfforward+shared+sm~udreg+verbose
munge@0.5.13
ncurses@6.1~symlinks+termlib
numactl@2.0.12
openmpi@3.1.5~cuda+cxx_exceptions fabrics=verbs ~java+legacylaunchers~memchecker+pmi schedulers=slurm ~sqlite3+thread_multiple+vt
openssl@1.1.1d+systemcerts
pcre@8.43~jit+multibyte+utf
perl@5.30.1+cpanm+shared+threads
python@3.7.6+bz2+ctypes+dbm~debug+libxml2+lzma~nis~optimizations+pic+pyexpat+pythoncmd+readline+shared+sqlite3+ssl~tix~tkinter~ucs4~uuid+zlib
rdma-core@20 build_type=RelWithDebInfo
readline@8.0
slurm@18-08-0-1~gtk~hdf5~hwloc~mariadb~pmix+readline
snappy@1.1.7 build_type=RelWithDebInfo patches=c9cfecb1f7a623418590cf4e00ae7d308d1c3faeb15046c2e5090e38221da7cd +pic+shared
sqlite@3.30.1~column_metadata+fts~functions~rtree
tar@1.32
unifyfs@develop+auto-mount+fortran+hdf5+pmi~pmix
xz@5.2.4
zlib@1.2.11+optimize+pic+shared

System information

As allways, your help is very much appreciated :)

Start by reproducing unifyfs start --share-dir=... with the reported Spack, Slurm, and Open MPI configuration, then trace how the server detects a supported resource manager. Done means the command no longer reports no supported resource manager detected under the documented Slurm setup.