git ignores config core.sshcommand but works fine with GIT_SSH_COMMAND=

Question

I would like to use the config to set sshCommand instead of the environment variable. But does not work Here is what happens

➜  GIT_SSH_COMMAND='ssh -i /var/www/level2.lu/www/git_id_rsa -F /dev/null' git ls-remote 
From [email protected]:syn2cat/Level2.lu.git
fcaa5a2e63499568dd916e7b18f950b311781bd0    HEAD
fcaa5a2e63499568dd916e7b18f950b311781bd0    refs/heads/master
a542061a64d3698d5da54d63456b26932fe549a2    refs/pull/1/head

➜  git config core.sshcommand                                                           
ssh -i /var/www/level2.lu/www/git_id_rsa -F /dev/null
➜  git ls-remote
Permission denied (publickey).
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

And debugging, it does not use the value from core.sshCommand

➜ GIT_TRACE=1 git ls-remote 
13:46:15.366401 git.c:344               trace: built-in: git 'ls-remote'
13:46:15.366564 run-command.c:334       trace: run_command: 'ssh' '[email protected]' 'git-upload-pack '\''syn2cat/Level2.lu.git'\'''

Versions

➜  lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 16.04.2 LTS
Release:    16.04
Codename:   xenial
➜  git --version
git version 2.7.4

Answer 1

The core.sshCommand option was added to git 2.10.0. You're running 2.7.4, which doesn't have that functionality. You'd need to upgrade to a newer Git if you wanted to use it.