utilisation pour migration main -> fallback

[isAAAc]

Bonjour,
si tu préfères que l'on développe sur le sujet sur le forum plutot que ici , juste dis le moi ;)
https://forum.yunohost.org/t/fallback-server-yunohost-app-for-your-backup-server/3482

voilà mon cas de figure,
j'ai un serveur ynh A qui tourne depuis des années (chez gandi)
j'ai un autre serveur B encore vierge, où je compte migrer mon serveur A.

Je pensais tenter d' utiliser fallback pour effectuer la migration.

Ma première question est sur le déploy en tant que tel : faut il que le serveur B soit configuré avant de déployer fallback sur le A ?

Ma seconde question relève de la configuration du serveur B : lors de l'install de ynh, il va m'etre demandé un ndd fqdn ... dois-je d'ors et déjà indiquer le ndd fqdn du serveur A lors de l'install de B ?

Ma troisième question relève des "backups" effectués par fallback sur A : les dernières modifications de ynh concernant les commandes de backup (avec --system et --data) sont elles bien implémentées ? (dans le sens de présentes)

Ma dernière question (pour le moment) concerne plus spécifiquement Nextcloud : les datas de Nextcloud sont elles bien prises en compte lors du fallback vers B ?

(au pire si j'ai bien compris, ça cassera pas mon serveur A ?)

Merci pour ton travail et par avance pour tes réponses ;)

isAAAc

[isAAAc]

work in progress

• Fallback installed on the "main server" (A) and on the "fallback server" (B),

• Fallback server is configured with the same fqdn during the installation of ynh

• no app installed on the Fallback server

status : waiting for the replication during this night

[maniackcrudelis]

Sorry for my late answer.
I think you're all good.

Data for nextcloud will probably be backup as well. It depends of nextcloud config actually. (the package, not the app).
Anyway, you can change your DNS from the server A to the B, and see if everything is ok. It won't break anything on A.
But on B, you'll need to do some clean after everything is ok, and especially to remove the app fallback, as well as its files and backup (if not removed by the script. After checking it, it would be removed by the script). So I guess just removing the app would be enough.

[isAAAc]

Sorry for my late answer.

No problem ;)

especially to remove the app fallback, as well as its files and backup (if not removed by the script. After checking it, it would be removed by the script). So I guess just removing the app would be enough.

Ok,

and what about all subdomains managed by Let's Encrypt ? i need to enforce the check when the DNS will be changed and propagated ?

i plan to do the migration this next night :)

[maniackcrudelis]

I don't remember having issues with my certificates (Except of course with Firefox which is fucking crazy with those certificates things...). So I guess the certificates would be backup by YunoHost.
Anyway, try it and you'll see.

[isAAAc]

yep i 'll give a feedback here when everything will be done ;)

[isAAAc]

i needed to increase the HD size because of backups (especially Nextcloud wich as a lot of data)

• enforce a last fallback "send" process on the main server

 /opt/yunohost/fallback/send_process# ./send_backup.sh -vvvv

• during this last backup, prepare the DNS zone change (don't forget to increment the zone file ;) ) : set the new ip of the "fallback server" instead of the "main" one
• launch the rebuild process on the fallback server :

/opt/yunohost/fallback/deploy_process# ./deploy_fallback.sh

• activate the new incremented DNS zone file (deployment of DNS zone can take hours, no scare about this)

• stop the old main server (but don't destroy it for now, if there is a trouble on the new main server (the old fallback one) we could need to reverse to the old server ... the rollback to the old DNS version, but increase then to a new zone file, cf DNS functionality for more details)

• verify every apps are functional

@maniackcrudelis :
i had many messages like this one : sh: 0: getcwd() failed: No such file or directory

i'm actually waiting for the DNS propagation, and verifying the apps, before removing the fallabck app

[isAAAc]

some let's encrypt issues, but i think the trouble is on proxmox side, renew with --no-checks works.

all apps are working ,

feel free ton contact me if help needed on migration via fallback app ,
and thx a lot @maniackcrudelis for your work !