This issue is similar to JENKINS-20750 and JENKINS-36269 but I'd like to reopen this since in our case it is not related to authentication and I can not reproduce these timeouts when manually running the git fetch command.

Here's the output inside jenkins:

Cloning the remote Git repository
Cloning repository ssh://git@server/diffusion/project.git
> git init <https://jenkins.1024.lu/job/project/ws/> # timeout=10
Fetching upstream changes from ssh://git@server/diffusion/project.git
> git --version # timeout=10
using GIT_SSH to set credentials Deprecated RSA key
> git fetch --tags --progress ssh://git@server/diffusion/project.git +refs/heads/:refs/remotes/origin/
ERROR: Timeout after 10 minutes
ERROR: Error cloning remote repo 'origin'
hudson.plugins.git.GitException: Command "git fetch --tags --progress ssh://git@server/diffusion/project.git +refs/heads/:refs/remotes/origin/" returned status code 143:
stdout:

And here's running a timed manual execution:

jenkins@fyrine:/tmp/foo$ git init
Initialized empty Git repository in /tmp/foo/.git/
jenkins@fyrine:/tmp/foo$ time git fetch --tags --progress ssh://git@server/diffusion/project.git +refs/heads/:refs/remotes/origin/
remote: Counting objects: 40991, done.
remote: Compressing objects: 100% (19199/19199), done.
remote: Total 40991 (delta 22730), reused 37934 (delta 20367)
Receiving objects: 100% (40991/40991), 1.25 GiB | 15.69 MiB/s, done.
Resolving deltas: 100% (22730/22730), done.
From ssh://git@server/diffusion/project
[…]

• [new branch] development -> origin/development
• [new branch] master -> origin/master
  […]
• [new branch] upload -> origin/upload
• [new tag] 1.0.5 -> 1.0.5
• [new tag] 1.32.0 -> 1.32.0
• [new tag] 1.75.0 -> 1.75.0

real 1m5.266s
user 0m44.864s
sys 0m11.000s

It takes a long time, but it doesn't take 10 minutes. I've tried this several times and I can confirm that only when run by Jenkins do these timeouts occur.