How to settle multy-local datanodes and with datas out of the tmp file on Mac ? Location = null - hadoop

Question

(first participation, please do not hesite to ask further elements)
I try too follow a tuto (https://openclassrooms.com/fr/courses/4467481-creez-votre-data-lake/4509436-deployez-hdfs-en-production-et-passez-a-l-echelle) to create a multi datanode on my laptop.
First we start with a namenode and one data node, then we add other data nodes.
The problem seems to be in two steps :
- During the namenode -format : I have a "location = null ??"
- I can run two datanodes but not two or more
The protocol is for the first part (1 datanode) :
Edit core-site.xml
Edit hdfs-site.xml
Create the folders corresponding the previous path edition
namenode -format
lunch namenode
lunch datanode
Second part (Three new datanodes) :
Create config files for new datanodes
lunch namenode
lunch datanodes : ./bin/hdfs datanode -conf ./etc/hadoop/datanode1.xml
NB : I define new folder for the data because we don't want them in the tmp file.
In the second part of the protocol, configuration files are edited (cf files) and we lunch the datanodes with. Thus, is the "dfs.data.dir" part in the hdfs-site file useless for more than one datanode ?
Issues :
When I do namenode -format i have these ligne : "Re-format filesystem in Storage Directory root= /Users/XXXXX/code/hdfs/namenode; location= null ? (Y or N)." I do Y
At this point, i don't understand the location = null ? It is not present in the tutorial, thus i think that my path is not ok. If I double chekcs my files, it appears to be ok.
Then i run my namode : It is ok
Then i run my firts datanode : It is ok
But when i run my seconde data node : Not ok : "datanode is running as process 72080. Stop it first and ensure /tmp/hadoop-XXXX-datanode.pid file is empty before retry"
I tend to think that it is all related to a path issue.
I looked in my tmp folder, and there is the .pid files. I don't understand because i though that i decide not to use the tmp files thanks to the change in my configuration
Here my files :
hdfs-site :
`<configuration>
<property>
<name>dfs.name.dir</name>
<value>/Users/XXXX/code/hdfs/namenode/</value>
</property>
<property>
<name>dfs.data.dir</name>
<value>/Users/XXXX/code/hdfs/datanode/</value>
</property>
</configuration>`
Core-site
`<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<configuration>
<property>
<name>fs.defaultFS</name>
<value>hdfs://localhost:9000</value>
</property>
</configuration>`
DatanodeX
`<configuration>
<property>
<name>dfs.datanode.address</name>
<value>0.0.0.0:50012</value>
</property>
<property>
<name>dfs.datanode.http.address</name>
<value>0.0.0.0:50077</value>
</property>
<property>
<name>dfs.datanode.ipc.address</name>
<value>0.0.0.0:50022</value>
</property>
<property>
<name>dfs.data.dir</name>
<value>/Users/XXXX/code/hdfs/datanode2/</value>
</property>
</configuration>
`