Should I care about this error "failed to link /usr/bin/psql [...]exists and it is not a symlink"? - Mailing list pgsql-admin

Hi all,

I'm installing postgres 9.6 in a CentOS 7 computer that already has postgres v9.2 installed (version that comes with CentOS installer) and I've seen the message of this mail's subject. It's the second machine where I see it, but previous one was a development server and I passed over it. But now I'm trying to make a guide to take this procedure to a Production server. I understand what this error is telling me, what I'm missing is if this has or can have any side effects.

The full installation log is (sorry for the parts in Spanish but I guess is more or less legible, if translation needed please ask):

[root@test-replicas ~]# yum install postgresql96-server
[....]
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction Instalando    : postgresql96-libs-9.6.16-2PGDG.rhel7.x86_64                                                                                                                                            1/3  Instalando    : postgresql96-9.6.16-2PGDG.rhel7.x86_64                                                                                                                                                 2/3 
failed to link /usr/bin/psql -> /etc/alternatives/pgsql-psql: /usr/bin/psql exists and it is not a symlink
failed to link /usr/bin/clusterdb -> /etc/alternatives/pgsql-clusterdb: /usr/bin/clusterdb exists and it is not a symlink
failed to link /usr/bin/createdb -> /etc/alternatives/pgsql-createdb: /usr/bin/createdb exists and it is not a symlink
failed to link /usr/bin/createlang -> /etc/alternatives/pgsql-createlang: /usr/bin/createlang exists and it is not a symlink
failed to link /usr/bin/createuser -> /etc/alternatives/pgsql-createuser: /usr/bin/createuser exists and it is not a symlink
failed to link /usr/bin/dropdb -> /etc/alternatives/pgsql-dropdb: /usr/bin/dropdb exists and it is not a symlink
failed to link /usr/bin/droplang -> /etc/alternatives/pgsql-droplang: /usr/bin/droplang exists and it is not a symlink
failed to link /usr/bin/dropuser -> /etc/alternatives/pgsql-dropuser: /usr/bin/dropuser exists and it is not a symlink
failed to link /usr/bin/pg_basebackup -> /etc/alternatives/pgsql-pg_basebackup: /usr/bin/pg_basebackup exists and it is not a symlink
failed to link /usr/bin/pg_dump -> /etc/alternatives/pgsql-pg_dump: /usr/bin/pg_dump exists and it is not a symlink
failed to link /usr/bin/pg_dumpall -> /etc/alternatives/pgsql-pg_dumpall: /usr/bin/pg_dumpall exists and it is not a symlink
failed to link /usr/bin/pg_restore -> /etc/alternatives/pgsql-pg_restore: /usr/bin/pg_restore exists and it is not a symlink
failed to link /usr/bin/reindexdb -> /etc/alternatives/pgsql-reindexdb: /usr/bin/reindexdb exists and it is not a symlink
failed to link /usr/bin/vacuumdb -> /etc/alternatives/pgsql-vacuumdb: /usr/bin/vacuumdb exists and it is not a symlink Instalando    : postgresql96-server-9.6.16-2PGDG.rhel7.x86_64                                                                                                                                          3/3  Comprobando   : postgresql96-libs-9.6.16-2PGDG.rhel7.x86_64                                                                                                                                            1/3  Comprobando   : postgresql96-server-9.6.16-2PGDG.rhel7.x86_64                                                                                                                                          2/3  Comprobando   : postgresql96-9.6.16-2PGDG.rhel7.x86_64                                                                                                                                                 3/3 

Instalado: postgresql96-server.x86_64 0:9.6.16-2PGDG.rhel7                                                                                                                                                            

Dependencia(s) instalada(s): postgresql96.x86_64 0:9.6.16-2PGDG.rhel7                                                           postgresql96-libs.x86_64 0:9.6.16-2PGDG.rhel7                                                          

¡Listo!
[root@test-replicas ~]# ls -l /usr/bin/psql /etc/alternatives/pgsql-psql
lrwxrwxrwx. 1 root root     23 dic  3 12:37 /etc/alternatives/pgsql-psql -> /usr/pgsql-9.6/bin/psql
-rwxr-xr-x. 1 root root 449280 nov  6  2016 /usr/bin/psql

I've searched this error, but the only thing I've found is something about alternatives system, and the command update-alternatives. But I don't fully understand this system (I'm used to Windows) and this means that when using the command I'm not sure about what I'm doing, and I can't go to a Production environment like this. An alternative to this could be copy all these files to another location and replace them with links to the copies. But this solution looks a bit ugly (don't know how to express better :D).

Should I go the easy way (copy files and replace original ones with links), is better the first option (update-alternatives) or is there another solution?

Thank you for your time,

Ekaterina