How to fast forward a branch when being offline

Question

How do I fast forward a branch, when I git fetched during I was online and now I'm offline and want to fast forward to the state I fetched earlier.

For example I'm offline and do the following:

$ git checkout develop
Switched to branch 'develop'
Your branch is behind 'origin/develop' by 37 commits, and can be fast-forwarded.
  (use "git pull" to update your local branch)

When trying to use git pull I get:

$ git pull
ssh: Could not resolve hostname <hostname>: Name or service not known
fatal: Could not read from remote repository.

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

What command do I need to use in this case?

Answer 1

git pull is a shortcut for git fetch followed by git merge.

Only git fetch accesses to the remote repository (and requires a network connection if the remote repository is on a different computer). git merge operates only with the data that already exists on your computer; it doesn't care about your network connection at all.

Since you already did git fetch all you need is to run the other half: git merge

Answer 2

Since git pull is basically git fetch + git merge and you already did fetch and can't do it again while offline, you just need to do git merge origin/develop.

Alternatively you can do git reset --hard origin/develop which will work even if there is no fast-forward.

Edit: More options. Another way is to do git branch -f develop origin/develop before switching to it - you can't alter current branch, but you can "update" any branch to any state as long as it is not current. For current branch you have to use git reset.