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SLAC Network

firewall

Bastion hosts:

jump.slac.stanford.edu

rocky9.slac.stanford.edu

nx4.slac.stanford.edu

fastx.slac.stanford.edu

s3dflogin.slac.stanford.edu

s3dfnx.slac.stanford.edu

SLAC Network

Controls network

- Local, no internet access

mcclogin

https://confluence.slac.stanford.edu/spaces/SCSPub/pages/269124580/SSH

facet-srv01

facet-srv20

iana, s3dfdtn….

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Remote connection

ssh
GUI:

FastX: https://slacprod.servicenowservices.com/kb_view.do?sysparm_article=KB0012877� Desktop client or browser: https://fastx.slac.stanford.edu:3300
NoMachine: https://slacprod.servicenowservices.com/kb_view.do?sysparm_article=KB0011831
Don’t store anything on FastX or NoMachine – it gets reset every month

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FACET-II controls network access

https://confluence.slac.stanford.edu/display/FACET/Remote+access+to+facethome+and+facet-srv01

Follow steps to have your account granted access to facet-srv01

facethome is a hub for FACET controls

Get to controls network (e.g. FastX, ssh mcclogin, ssh fphysics@facet-srv01, select profile)
Launch facethome

Experiment data (https://confluence.slac.stanford.edu/display/FACET/Data+Retrieval)

Initially saved to FACET NAS (controls network only)
Uploaded daily to SLAC central /nfs/slac/g/facetdata/nas/, mounted on s3df to /fs/gpfs/slac/staas/fs1/g/facetdata/nas/
Data will soon be moved to /sdf/data/facet/

Your home directory is synced between s3df and mcclogin, but not facet-srv01�

More info: https://confluence.slac.stanford.edu/display/FACET/FACET-II+Home

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Git (and CVS) at FACET-II

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Why do we need a version control system?

track the changes you make to files, so you have a record of what has been done, and you can revert to specific versions should you ever need to.
makes collaboration easier, allowing changes by multiple people to all be merged into one source.

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GIT vs CVS

Git is a distributed version control system
Developed by Linus Torvalds in 2005.

CVS is a centralized version control system
Developed by Dick Grune in 1986.
‘Concurrent Versions System’

Repository

Local

copy 1

Local

copy 2

Local

copy N

Centralized version system (CVS, SVN,...)

Repository

Local repo

Local

copy 1

Local

copy 2

Local

copy N

Distributed version system (Git, Mercurial,...)

Developer 1

Developer 2

Developer N

Central Server

Remote Server

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Version control systems for software

We use both Git and CVS to manage the changes that individuals make to code that runs in the FACET-II control system
Key language:

Repository and branches
Commit, pull, push, checkout
Master and “Production”

Image from: https://training.github.com/downloads/github-git-cheat-sheet.pdf

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Git or CVS???

EDM -> CVS
PyDM -> Git
Matlab GUI -> Git

PyDM panel

EDM panel

facethome

Matlab GUI panel

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What does this look like for FACET?

‘master’ matlabTNG repository

‘production’ copy

Your local copy

Edit files -

Commit(s) -

Merge/check for conflicts -

Edit files (if needed) -

Push changes to master -

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What does this look like for FACET – with many users

‘master’ matlabTNG repository

‘production’ copy

My code changes

Someone else’s work

Your local copy

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Where to find more information

Confluence:

Ask each other!

Both Git and CVS are widely used, so lots of information is available online

https://github.com/git-guides
Google: ‘git cheatsheet’

Your mentor (or anyone at FACET-II)

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Get access to both Git and CVS

Request access from Ken Brobeck: brobeck@slac.stanford.edu

Tell him you are a FACET summer intern, your unix username, and that you need access to: /afs/slac/g/cd/swe/git/repos/slac/FACET

(and facet CVS repositories for edm, if needed)

Set up your home git_work and cvs_work directories on facet-srvXX (i.e.: mkdir git_work)

Make sure you select your profile at login, or use the set_profile command

Locations of repositories:

Matlab files: /afs/slac/g/cd/swe/git/repos/slac/FACET/matlabTNG.git

Mirrored here: https://github.com/slaclab/facet-matlabTNG
Production version: /usr/local/facet/tools/matlabTNG/

Python files: /afs/slac/g/cd/swe/git/repos/slac/pydm_displays/user-facet.git

Production: /usr/local/facet/tools/pydm/display/user-facet/

Matlab tools: /afs/slac/g/cd/swe/git/repos/slac/matlab/hla/facet/toolbox.git

Production: /usr/local/facet/tools/matlab/toolbox/

CVS: EDM files: tools/edm/...

Production: /usr/local/facet/tools/...

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Git Step 1: Clone a repository to your git_work directory

•This puts a local repo and local copy onto your facet-srv01 account

•This is now your own “private” version that you will work on

•But – it is a clone at this specific time, new changes are not automatically updated

• Later on use: git pull to update your local copy to include the latest code updates.

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Git Step 2: Typical workflow for editing a file

Note – if the file didn’t already exist in the repo, then you can use: git add README.md before the commit to add it.

1) Edit the file

2) Commit the changes with a USEFUL comment

3) Uploads your local copy commits to the remote server. i.e. publishes your changes

nano

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Git Step 3: Update the production repo

You have now pushed your changes to the master repo
But… the “production” repository that runs on the control system is not automatically updated
So you need to: git pull the changes on the production system:

1) Get to the right directory

2) Pull the latest version of the master repository

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Git workflow summary

From your git work directory

fphysics@facet-srv01 ~/<user>/gitwork/matlabTNG ]$

Commands:

git pull origin master
edit your file
git add file.m (only if it’s a new file that doesn’t exist on the repository)
git commit –m “This a descriptive comment” file.m
git pull origin master
git push origin master

cd /usr/local/facet/tools/matlabTNG/
git pull

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CVS Step 1 - Workflow is similar with CVS

First – need to checkout the latest version into your cvs_work directory:

Always check to make sure the file is up-to-date before making changes and committing.

1) Checks out the current version of the file to you.

Do not forget this step!

2) The –A argument checks if your repo is current

No output means current
The ‘P’ means you need to pull changes!

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CVS Step 2 – Edit your file and commit

Edit the file, then commit:

If this is a new file, then you need to add it to the repository first:

1) Commit the changes with a USEFUL comment

1) Adds the file to the repo

2) Commits the new file

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CVS Step 3 – Update the production version

For EDM files, change to the production directory and update:

Moves the new version to the production machine

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CVS workflow summary

From your cvs work directory, and into the directory where the file resides:

fphysics@facet-srv01 ~/<user>/cvswork/tools/../../.. ]$

Commands:

cvs update -A file.edl
edit your file
cvs add file.edm (only if it’s a new file that doesn’t exist on the repository)
cvs commit –m “This a descriptive comment” file.edl

cvs2prod file.edl

-- or --

cd $TOOLS/edm/display/facet
cvs update file.edl

Repository

Local copy

update

commit

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Extra steps

Make an account on one of the version control system sites:
www.bitbucket.org
www.github.com
www.gitlab.com

Install git client on your computer (command line or GUI)
https://git-scm.com/downloads

Test various git commands and workflows:
Make extra branch, edit/create files in both branches, merge back
Resolve merge conflict - same file edited in different local copies�……

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Final thoughts

Questions?

Remember:

Make sure that you have access to git

if not, then please contact Ken Brobeck from your SLAC email account

Select your own profile when you log in

Always make sure that you have the latest version before you start making your own edits
Add useful comments when committing
Don’t forget to push changes to production

Don’t store huge amounts of data on the facet-srvXX machines (<10GB)

It’s ok if required for development (code is fine, large FACET image datasets can be 10’s-100’s of GB)

Don’t store anything on FastX – it gets reset every month

FACET-II Summer Intern Program - Intro to computing at FACET-II