2FA for Bitbucket Server supports LFS, however if the repository requires a "secured in browser through 2FA" and the 2FA session length is short enough to expire during the LFS operation this may cause issues. This is reported in 

Potential Workarounds

• Add in a "whitelist' rule of "Path containing" git/info/lfs . This will exclude the LFS operations from participating in the LFS operations.
• For the Repositories that have LFS enabled, don't enable the "Secured in browser through 2FA".

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