Différences

Ci-dessous, les différences entre deux révisions de la page.

--- tech:notes_etcd [2026/06/04 09:13] – Jean-Baptiste
+++ tech:notes_etcd [2026/06/04 10:15] (Version actuelle) – Jean-Baptiste
@@ Ligne 1: / Ligne 1: @@
+<!DOCTYPE markdown>
+{{tag>Brouillon DB KV}}
+# Notes etcd
+Voir aussi :
+* [[Notes CouchDB|CouchDB]]
+Python :
+* https://www.dasblinkenlichten.com/python-pieces-working-with-etcd/
+## Intro
+* https://etcd.io/
+* https://etcd.io/docs/v3.5/dev-guide/interacting_v3/
+* https://www.ionos.fr/digitalguide/hebergement/aspects-techniques/quest-ce-quetcd/
+* https://www.blackcreeper.com/kubernetes/etcd-decouverte-et-premiers-pas/
+## Install
+* http://play.etcd.io/install
+* https://www.digitalocean.com/community/tutorials/how-to-set-up-and-secure-an-etcd-cluster-with-ansible-on-ubuntu-18-04-fr
+* https://docs.okd.io/3.11/admin_guide/assembly_replace-etcd-member.html
+~~~bash
+apt install etcd-client
+apt-get install etcd
+~~~
+## Config
+### Droits
+https://etcd.io/docs/v3.5/demo/
+## Exemples basiques
+Lancement
+~~~bash
+etcd
+~~~
+Connexion
+~~~bash
+etcdctl --endpoints http://127.0.0.1:2379 get /
+~~~
+Put
+~~~bash
+etcdctl put greeting "Hello, etcd"
+~~~
+Get
+~~~bash
+ETCDCTL_API=3 etcdctl get greeting
+etcdctl get foo --print-value-only
+etcdctl get --prefix --rev=4 foo
+etcdctl watch foo --hex
+~~~
+~~~bash
+etcdctl --no-sync --peers https//plop1.lan:10835,https//plop2.lan:10836 -u username:password ls /
+alias e='etcdctl --ca-file ~/compose_etcd.pk --no-sync --peers https://aws-us-east-1-portal10.dblayer.com:10835,https://aws-us-east-1-portal11.dblayer.com:27265 -u root:*********'
+~~~
+~~~bash
+etcdctl mk x 3
+etcdctl mk y 123
+etcdctl ls
+etcdctl get /y
+etcdctl set new 6
+etcdctl set d/a 4
+etcdctl set d/b 5
+etcdctl ls d
+etcdctl rm --recursive d
+# TTL of 5 seconds
+etcdctl mk e 4 --ttl "5"
+~~~
+~~~bash
+export ETCDCTL_API=3
+export ETCDCTL_ENDPOINTS=$(minikube service example-etcd-cluster-client-service --url)
+~~~
+backup (cluster & local)
+Voir https://etcd.io/docs/v3.5/op-guide/recovery/
+~~~bash
+ETCDCTL_API=3 etcdctl --endpoints $ENDPOINT snapshot save snapshot.db #--cacert /etc/ssl/etcd/ca.crt --cert /etc/ssl/etcd/client.crt --key /etc/ssl/etcd/client.key
+~~~
+Verify the snapshot:
+~~~bash
+ETCDCTL_API=3 etcdctl --write-out=table snapshot status snapshotdb
+~~~
+Restore (local)
+~~~bash
+ETCDCTL_API=3 etcdctl snapshot restore snapshot.db
+~~~
+grpc-proxy
+~~~bash
+etcd grpc-proxy start --endpoints=infra0.example.com,infra1.example.com,infra2.example.com --listen-addr=127.0.0.1:2379
+~~~
+## Tuning
+IO
+~~~bash
+# best effort, highest priority
+sudo ionice -c2 -n0 -p `pgrep etcd`
+~~~
+CPU
+~~~bash
+echo performance | tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
+~~~
+## Diag
+~~~bash
+sudo chown -R etcd:etcd /var/lib/etcd
+sudo systemctl start etcd
+~~~
+List the cluster member:
+~~~bash
+etcdctl --endpoints=http://${NODE1}:2379 member list
+~~~
+## Client API Python
+https://www.dasblinkenlichten.com/python-pieces-working-with-etcd/
+## Autre
+### pas de type list ?
+Voir https://github.com/ake-persson/etcdtool
+etcd doesn't support list's, this is handled by using the index as the key:
+JSON Input:
+~~~javascript
+{
+    "users": [
+        { "username": "jblack", "first_name": "John", "last_name": "Blackbeard" },
+        { "username": "ltrier", "first_name": "Lars", "last_name": "Von Trier" }
+    ]
+}
+~~~
+Result in etcd:
+~~~
+users/0/username: jblack
+users/0/first_name: John
+users/0/last_name: Blackbeard
+users/1/username: ltrier
+users/1/first_name: Ludwig
+users/1/last_name: Von Treimer
+~~~