Answers

When is Renest the wrong tool?

When the problem isn't moving a setup that already works onto another Linux GPU machine. Housekeeping on one PC, a Windows-to-Windows move, a first install that never worked, a production deployment, or a framework other than ComfyUI, kohya_ss or LLaMA-Factory all have better answers, and this page gives them.

What Renest is for, in one paragraph

Renest is for one job: you have ComfyUI, kohya_ss or LLaMA-Factory working on a Linux machine with an NVIDIA GPU, usually a rented one, and you want that working setup back on another machine. It keeps the files and a reinstallable record of the dependencies, checks every file when it comes back, and tests whether the app works on the new machine. If your problem is anything else, one of the answers below is simpler.

I want to move my models to another drive on the same PC

Point ComfyUI at the new folder; you don't need to move the install. Two ways:

extra_model_paths.yaml. In the ComfyUI folder, copy extra_model_paths.yaml.example to extra_model_paths.yaml and add a section whose base_path is the new location, with one line per model type, for example checkpoints: models/checkpoints/. Restart ComfyUI.
A directory junction on Windows. Move the models folder to the new drive, then create a junction where it used to be, so ComfyUI sees the same path. From a Command Prompt:

Shell

$ mklink /J "C:\ComfyUI\models" "D:\ComfyUI-models"

The first path is where ComfyUI expects the folder, and must not exist any more; the second is where the files now live. On Linux, a symbolic link (ln -s) does the same.

I want my models and workflows to survive ComfyUI updates

Keep them outside the install, so an update only replaces the program:

Models: point extra_model_paths.yaml at a folder outside the install, as above.
Workflows and settings: recent ComfyUI versions have launch options that move the user, output and input folders outside the install; python main.py -h lists them.
Custom nodes have to stay inside each install, in its own custom_nodes folder, with their packages in that install's Python.
Before a big update, keep a copy of the whole program folder. Going back is then a rename.

I run several ComfyUI installs and want them to share models

Models can be shared; custom nodes can't. Point every install's extra_model_paths.yaml at one model folder. Each install still loads custom nodes from its own custom_nodes folder and needs their packages in its own Python. Pointing a second install at the first one's node folder doesn't install those packages there.

I clicked reinstall. Are my models and custom nodes gone?

Move custom_nodes, models and user out of the install folder before the reinstall touches them, and move them back afterwards. Models usually work at once. Custom nodes often need their packages installed again, because the reinstall replaced the Python they lived in; ComfyUI-Manager or the node's requirements.txt does that. If the reinstall has already overwritten or deleted the files, there is no undo. Restore them from a backup if you have one.

I ran pip install and ComfyUI Portable still says the package is missing

The package went into a different Python. ComfyUI Portable runs its own embedded Python, and a bare pip or python -m pip installs into whichever Python is first on your path. From the ComfyUI_windows_portable folder, use the embedded one:

Shell

$ python_embeded\python.exe -s -m pip install <package>

If that Python has no pip at all, ComfyUI-Manager can't install anything either. Install pip into that same python.exe, then restart.

I'm moving ComfyUI from one Windows PC to another

Copy the whole Portable folder. The embedded Python, the custom nodes and their packages are all inside it, so it usually runs on the new PC as long as the GPU is from a family the same PyTorch build supports. Copy the model folder too, if it lives elsewhere, and update extra_model_paths.yaml if its location changed. Renest restores onto Linux machines with an NVIDIA GPU, and the desktop app isn't built yet, so it doesn't help with this move.

ComfyUI, kohya_ss or LLaMA-Factory has never worked for me

Renest can't help with a first install. It only carries a setup from a run that already worked: it doesn't resolve dependency conflicts, choose versions, or recommend models, templates or training settings. Get it working once with the project's own install guide or a ready-made template on your GPU provider. After that, Renest can keep the working version for the next machine.

I want a serverless endpoint or a production deployment

Build a Docker image with your dependencies installed, and keep the models on a volume or download them at start-up. That is what serverless GPU platforms expect. Renest isn't a deployment platform. It restores a setup onto a GPU machine you rent, for you to work on.

I use A1111, Forge, diffusion-pipe, musubi-tuner, ai-toolkit or Axolotl

Renest doesn't support them. It is built for three named frameworks: ComfyUI for image generation, and kohya_ss and LLaMA-Factory for fine-tuning. The checks described in these docs, such as which custom nodes loaded or whether training wrote a file, are written for those three, and we don't test anything else.

Other things Renest doesn't do

Make the same seed give the same image on another GPU. Files and versions come back as they were, and different hardware can still produce different pixels. Why: Same GPU, two images.
Run your setup on a GPU generation it never ran on. Renest doesn't swap your PyTorch version. Get it working on the new card, then pack it there. See Errors after changing GPU.
Repair a broken rented machine, such as a GPU that doesn't answer or a driver that's too old. The fix is another machine, and the same restore command works there.
Fix a workflow file someone sent you. See Red nodes and empty model lists.
Make downloads faster. The models still have to come down onto the new machine. What a restore saves is the reinstalling and the trial and error.
Replace a network volume you're happy with. If you always come back to the same region of the same provider and your setup survives restarts, keep using it.