Consul » History » Version 4
Peter Amstutz, 10/26/2016 01:14 AM
| 1 | 1 | Peter Amstutz | h1. Consul |
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| 2 | |||
| 3 | 3 | Peter Amstutz | h2. Services |
| 4 | 2 | Peter Amstutz | |
| 5 | Each service must have a unique id, but may have a common name, for example: |
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| 6 | |||
| 7 | <pre> |
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| 8 | { |
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| 9 | "service": { |
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| 10 | "id": "zzzzz-bi6l4-ydim6qekt9ut47f", |
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| 11 | "name": "keep", |
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| 12 | "port": 80 |
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| 13 | } |
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| 14 | } |
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| 15 | </pre> |
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| 16 | |||
| 17 | <pre> |
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| 18 | { |
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| 19 | "service": { |
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| 20 | "id": "zzzzz-bi6l4-9e7boja2v94hfj5", |
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| 21 | "name": "keep", |
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| 22 | "port": 80 |
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| 23 | } |
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| 24 | } |
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| 25 | </pre> |
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| 26 | |||
| 27 | A query on the "keep" service returns multiple nodes: |
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| 28 | |||
| 29 | <pre> |
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| 30 | $ curl http://localhost:8500/v1/catalog/service/keep | jq . |
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| 31 | [ |
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| 32 | { |
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| 33 | "Node": "debian", |
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| 34 | "Address": "127.0.0.1", |
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| 35 | "TaggedAddresses": { |
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| 36 | "lan": "127.0.0.1", |
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| 37 | "wan": "127.0.0.1" |
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| 38 | }, |
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| 39 | "ServiceID": "zzzzz-bi6l4-9e7boja2v94hfj5", |
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| 40 | "ServiceName": "keep", |
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| 41 | "ServiceTags": [], |
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| 42 | "ServiceAddress": "", |
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| 43 | "ServicePort": 443, |
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| 44 | "ServiceEnableTagOverride": false, |
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| 45 | "CreateIndex": 7, |
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| 46 | "ModifyIndex": 7 |
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| 47 | }, |
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| 48 | { |
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| 49 | "Node": "debian", |
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| 50 | "Address": "127.0.0.1", |
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| 51 | "TaggedAddresses": { |
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| 52 | "lan": "127.0.0.1", |
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| 53 | "wan": "127.0.0.1" |
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| 54 | }, |
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| 55 | "ServiceID": "zzzzz-bi6l4-ydim6qekt9ut47f", |
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| 56 | "ServiceName": "keep", |
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| 57 | "ServiceTags": [], |
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| 58 | "ServiceAddress": "", |
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| 59 | "ServicePort": 80, |
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| 60 | "ServiceEnableTagOverride": false, |
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| 61 | "CreateIndex": 6, |
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| 62 | 1 | Peter Amstutz | "ModifyIndex": 6 |
| 63 | } |
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| 64 | ] |
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| 65 | </pre> |
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| 66 | 3 | Peter Amstutz | |
| 67 | h2. Configuration management |
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| 68 | |||
| 69 | Store configuration in Consul k/v store. Union of configuration for API server, workbench, etc. |
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| 70 | |||
| 71 | Use https://github.com/hashicorp/consul-template to write configuration files for individual components and automatically restart services when configuration files are updated by consul-template. |
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| 72 | |||
| 73 | h2. Deployment |
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| 74 | |||
| 75 | # Service packages have dependency on consul and consul-template. |
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| 76 | 4 | Peter Amstutz | # Consul and consul-template run automatically from systemd unit. |
| 77 | # Orchestration system (terraform? puppet?) installs/updates packages, installs /etc/consul.d/service.json (e.g. /etc/consul.d/keepproxy.json), consul-template for configuration file. (Unclear if service.json and consul-template should be part of package or installed some other way.) |
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| 78 | |||
| 79 | 3 | Peter Amstutz | |
| 80 | h2. Transition to Consul |
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| 81 | |||
| 82 | API endpoints currently used for service discovery such as the keep services table should be removed from the database and instead query Consul on the backend. |