I am looking for a solution to update tags without redeploying the nomad job

Consul
1

Hi guys,

My hashistack works as expected and this is a very good point ! :slight_smile:

But I am looking for a solution to update tags without redeploying the nomad job.

This is an extract of one of my nomad job :

...
"Services": [
  {
    "Name": "wwwdomaincom",
    "TaskName": "",
    "PortLabel": "caddy",
    "AddressMode": "auto",
    "Address": "",
    "EnableTagOverride": false,
    "Tags": [
      "traefik.enable=true",
      "traefik.http.routers.wwwdomaincom.tls=true",
      "traefik.http.routers.wwwdomaincom.tls.certresolver=myresolver",
      "traefik.http.routers.wwwdomaincom.tls.options=mintls12@file",
      "traefik.http.routers.wwwdomaincom.entrypoints=https",
      "traefik.http.routers.wwwdomaincom.rule=Host(`www.domain.com`)",
      "traefik.http.middlewares.wwwdomaincom.redirectscheme.scheme=https",
      "traefik.http.middlewares.wwwdomaincom.redirectscheme.permanent=true",
      "traefik.http.middlewares.wwwdomaincom-whistelist.ipwhitelist.sourcerange=a.b.c.d",
      "traefik.http.routers.wwwdomaincom.middlewares=wwwdomaincom-whistelist@consulcatalog",
    ],
  ...

As you can see, I use traefik as a reverse proxy for my containers infrastructure.
Tags are scrapped by traefik from consul and my service is working.

But every time I wish to add or whitelist a new IP address, I need to redeploy my nomad job. Job is restarting, deployment happens, unavailabilty happens, etc.

I am looking for a solution to update tags without redeploying the nomad job.

I tried it in a different way:

  • I removed tags from my nomad job
  • I use a curl (it was an ansible module btw, community.general.consul) command to submit a new service with the same name: wwwdomaincom

This solution works but I need to submit a service address and a service port. These values are dynamically provided by nomad, so it’s finally more complicated, even worst…

Note: this job is a single one, no blue/green or canary deployment.

I hope you understand my needs :grinning:

How do you manage this situation ?

Do you use all the magic from nomad and consul ?
Do you set up tags in a different way ?

Thanks

2

Hey, just to let your know that I found my solution here by using a “check and set” transaction.

On nomad side, EnableTagOverride is a nice solution, it reduces downtime and it solved my problem. But another side effect appears, if the linux host restarts or if nomad reschedules the job for any reasons, tags from my nomad job are saved to consul. All modifications made with transactions are lost.