RE: pg_upgrade -c cannot be run if old cluster is running - Mailing list pgsql-docs

Tried (as postgres)
/usr/pgsql-15/bin/pg_upgrade --check -b /usr/pgsql-10/bin/ -B /usr/pgsql-15/bin -d /var/lib/pgsql/10/data -D
/mnt/pgdata/pgdirbc15-p5432 -P5455 -Upostgres -v 
Running in verbose mode
Performing Consistency Checks
-----------------------------
Checking cluster versions                                   ok
Current pg_control values:

pg_control version number:            1002
Catalog version number:               201707211
Database system identifier:           6631834114473972710
Latest checkpoint's TimeLineID:       1
Latest checkpoint's full_page_writes: on
Latest checkpoint's NextXID:          0:555
Latest checkpoint's NextOID:          13809
Latest checkpoint's NextMultiXactId:  1
Latest checkpoint's NextMultiOffset:  0
Latest checkpoint's oldestXID:        548
Latest checkpoint's oldestXID's DB:   1
Latest checkpoint's oldestActiveXID:  0
Latest checkpoint's oldestMultiXid:   1
Latest checkpoint's oldestMulti's DB: 1
Latest checkpoint's oldestCommitTsXid:0
Latest checkpoint's newestCommitTsXid:0
Maximum data alignment:               8
Database block size:                  8192
Blocks per segment of large relation: 131072
WAL block size:                       8192
Bytes per WAL segment:                16777216
Maximum length of identifiers:        64
Maximum columns in an index:          32
Maximum size of a TOAST chunk:        1996
Size of a large-object chunk:         2048
Date/time type storage:               64-bit integers
Float4 argument passing:              by value
Float8 argument passing:              by value
Data page checksum version:           0


Values to be changed:

First log segment after reset:        000000010000000000000002
Current pg_control values:

pg_control version number:            1300
Catalog version number:               202209061
Database system identifier:           7410372953202657258
Latest checkpoint's TimeLineID:       1
Latest checkpoint's full_page_writes: on
Latest checkpoint's NextXID:          0:732
Latest checkpoint's NextOID:          16387
Latest checkpoint's NextMultiXactId:  1
Latest checkpoint's NextMultiOffset:  0
Latest checkpoint's oldestXID:        716
Latest checkpoint's oldestXID's DB:   1
Latest checkpoint's oldestActiveXID:  0
Latest checkpoint's oldestMultiXid:   1
Latest checkpoint's oldestMulti's DB: 1
Latest checkpoint's oldestCommitTsXid:0
Latest checkpoint's newestCommitTsXid:0
Maximum data alignment:               8
Database block size:                  8192
Blocks per segment of large relation: 131072
WAL block size:                       8192
Bytes per WAL segment:                16777216
Maximum length of identifiers:        64
Maximum columns in an index:          32
Maximum size of a TOAST chunk:        1996
Size of a large-object chunk:         2048
Date/time type storage:               64-bit integers
Float8 argument passing:              by value

Data page checksum version:           0


Values to be changed:

First log segment after reset:        000000010000000000000002
"/usr/pgsql-10/bin/pg_ctl" -w -l
"/mnt/pgdata/pgdirbc15/pg_upgrade_output.d/20240905T083735.457/log/pg_upgrade_server.log"-D "/var/lib/pgsql/10/data" -o
"-p5432 -b  -c listen_addresses='' -c unix_socket_permissions=0700 -c unix_socket_directories='/var/lib/pgsql'" start
>>"/mnt/pgdata/pgdirbc15/pg_upgrade_output.d/20240905T083735.457/log/pg_upgrade_server.log" 2>&1 

*failure*
There were problems executing ""/usr/pgsql-10/bin/pg_ctl" -w -l
"/mnt/pgdata/pgdirbc15/pg_upgrade_output.d/20240905T083735.457/log/pg_upgrade_server.log"-D "/var/lib/pgsql/10/data" -o
"-p5432 -b  -c listen_addresses='' -c unix_socket_permissions=0700 -c unix_socket_directories='/var/lib/pgsql'" start
>>"/mnt/pgdata/pgdirbc15/pg_upgrade_output.d/20240905T083735.457/log/pg_upg 
rade_server.log" 2>&1"
Consult the last few lines of "/mnt/pgdata/pgdirbc15/pg_upgrade_output.d/20240905T083735.457/log/pg_upgrade_server.log"
forthe probable cause of the failure. 

connection to server on socket "/var/lib/pgsql/.s.PGSQL.5432" failed: No such file or directory
Is the server running locally and accepting connections on that socket?

could not connect to source postmaster started with the command:
"/usr/pgsql-10/bin/pg_ctl" -w -l
"/mnt/pgdata/pgdirbc15/pg_upgrade_output.d/20240905T083735.457/log/pg_upgrade_server.log"-D "/var/lib/pgsql/10/data" -o
"-p5432 -b  -c listen_addresses=''  
-c unix_socket_permissions=0700 -c unix_socket_directories='/var/lib/pgsql'" start
Failure, exiting