原文链接 http://www.k8s.tips/tech/2015/11/30/git_sync_up_upstream/
注：以下为加速网络访问所做的原文缓存，经过重新格式化，可能存在格式方面的问题，或偶有遗漏信息，请以原文为准。
Configuring a remote for a fork
List the current configured remote repository for your fork.
$git remote -v
origin https://github.com/YOUR_USERNAME/YOUR_FORK.git (fetch)
origin https://github.com/YOUR_USERNAME/YOUR_FORK.git (push)
Specify a new remote upstream repository that will be synced with the fork.
$git remote add upstream https://github.com/ORIGINAL_OWNER/ORIGINAL_REPOSITORY.git
Verify the new upstream repository you've specified for your fork.
$git remote -v
origin https://github.com/YOUR_USERNAME/YOUR_FORK.git (fetch)
origin https://github.com/YOUR_USERNAME/YOUR_FORK.git (push)
upstream https://github.com/ORIGINAL_OWNER/ORIGINAL_REPOSITORY.git (fetch)
upstream https://github.com/ORIGINAL_OWNER/ORIGINAL_REPOSITORY.git (push)
Syncing a fork
Fetch the branches and their respective commits from the upstream repository. Commits to master will be stored in a local branch, upstream/master.
$git fetch upstream
remote: Counting objects: 75, done.
remote: Compressing objects: 100% (53/53), done.
remote: Total 62 (delta 27), reused 44 (delta 9)
Unpacking objects: 100% (62/62), done.
From https://github.com/ORIGINAL_OWNER/ORIGINAL_REPOSITORY
* [new branch] master -> upstream/master
Check out your fork's local master branch.
$git checkout master
Switched to branch 'master'
Merge the changes from upstream/master into your local master branch. This brings your fork's master branch into sync with the upstream repository, without losing your local changes.
$git merge upstream/master
Updating a422352..5fdff0f
Fast-forward
README | 9 -------
README.md | 7 ++++++
2 files changed, 7 insertions(+), 9 deletions(-)
delete mode 100644 README
create mode 100644 README.md
If your local branch didn't have any unique commits, Git will instead perform a "fast-forward":
$git merge upstream/master
Updating 34e91da..16c56ad
Fast-forward
README.md | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)