Re: push to backup repo periodically fails with "not fast forward"

> I have a repo on another disk that I ONLY use to backup my in-use
> local repo.  I have a post-commit hook that does the push (git push --
> all remote-repo-name)
>
>>git commit -a -m 'some change'
> Counting objects: 71, done.
> Compressing objects: 100% (26/26), done.
> Writing objects: 100% (29/29), 2.31 KiB, done.
> Total 29 (delta 12), reused 0 (delta 0)
> Unpacking objects: 100% (29/29), done.
> To file:///Volumes/Git/pose/main
>   22d7f10..0037aaf  bimonthly-frequency -> bimonthly-frequency
>  ! [rejected]        master -> master (non-fast forward)
> error: failed to push some refs to 'file:///Volumes/Git/pose/main'
> Created commit 0037aaf: Removed assertion that made no sense.
>  1 files changed, 0 insertions(+), 2 deletions(-)
>
> I'm using git as a front-end to Subversion, but I can't figure out why
> this is happening.
>
> The repo at /Volumes/Git/pose/main is NEVER pulled from or pushed to
> by anything other than my hook.  I can't understand why any push to it
> would NOT be a fast-forward.
>
> Any ideas how I can figure out what's going on?