# Ray cluster on PBS

**URL:** <https://discuss.ray.io/t/ray-cluster-on-pbs/1097>\
**Category:** Ray Core\
**Created:** [March 3, 2021, 1:22pm UTC](https://discuss.ray.io/t/ray-cluster-on-pbs/1097 "2021-03-03T13:22:14Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Michael](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.ray.io/michael/32/568_2.png) [@Michael](https://discuss.ray.io/u/Michael)\
**Post date:** [March 3, 2021, 1:22pm UTC](https://discuss.ray.io/t/ray-cluster-on-pbs/1097/1 "2021-03-03T13:22:14Z")

</div>

Hi, I am a new Ray user and still novice with Slurm / PBS.  
I would like to continue using my Dask workflows, by replacing the scheduler with Ray’s one. What I have done for the moment is creating the cluster with Dask distributed (only the cluster, not connecting the client).  
Then I’m launching some basic computations using .compute(scheduler=ray\_dask\_get).  
The computations run fine, however they are not distributed over the cluster (only run in parallel on the head node).  
I understand that the cluster should also not be launched with dask ? In that case, will all my dask computations run correctly ? (there are a lot in my code)

I have found into Ray"s documentation about running Ray on a PBS cluster. However, I can’t get the script to work with PBS (see [here](https://docs.ray.io/en/master/cluster/slurm.html))

Does anyone have any experience on this topic ?

More specifically I would be happy to simply manage to detect the head node and it’s IP by converting the code below to PBS

```
# Getting the node names
nodes=$(scontrol show hostnames "$SLURM_JOB_NODELIST")
nodes_array=($nodes)

head_node=${nodes_array[0]}
head_node_ip=$(srun --nodes=1 --ntasks=1 -w "$head_node" hostname --ip-address)

# if we detect a space character in the head node IP, we'll
# convert it to an ipv4 address. This step is optional.
if [["$head_node_ip" == *" "*]]; then
IFS=' ' read -ra ADDR <<<"$head_node_ip"
if [[${#ADDR[0]} -gt 16 ]]; then
  head_node_ip=${ADDR[1]}
else
 head_node_ip=${ADDR[0]}
fi
echo "IPV6 address detected. We split the IPV4 address as $head_node_ip"
fi
```