3.1 KiB
DNS
001 Recursor out off NAS
Status
done
Context
curently main local domain DNS is located on NAS.
goal:
- avoid DNS outtage in case of NAS reboot (my synology have 10 years and is a litle long to reboot) morever during NAS reboot we lost the adblock DNS in the nomad cluster because nomad depend of the NFS share.
- remove the direct redirection to service.consul DNS and the IPTABLE rule use to redirect port 53 on consul on gerard instead new DNS could be forward directly to an active consul node on port 8300
DNS software
need DHCP Dynamic update could redirect domain on other port than port 53
Decision
we will migrate Main Domain DNS from NAS to gerard (powerDNS) powerDNS provide two disting binaries one for authority server one other for recursor goal is to first migrate the recursice part from synology to a physical service and in second time migrate authority server in nmad cluster
Consequences
before to move authority server need to remove DB dns dependance (create db consul services) need to delete the iptable rule on gerard before deploy
002 each node request self consul client for consul dns query
Status
done
Context
to avoid a cluster failled in case of the DNS recursor default. I would like that each cluster client request their own consul client first to resolve consul DNS query
Decision
Implement sytemd-resolved on all cluster member and add a DNS redirection
Consequences
need to modify annsible system role for systemd-resolved activation and consul role for configure redirection
003 migrate authority DNS from NAS to cluster
Status
done
Context
we have curently three authority domain on NAS:
- ducamps.win
- ducamps.eu
- lan.ducamps.eu
we could migrate authority DNS in cluster ducamps.win and ducamps.eu are only use for application access so no dependence with cluster build need to study cluster build dependance for lan.ducamps.eu-> in every case in case of build from scratch need to use IP need keepalive IP and check if no conflict if store on same machine than pihole->ok don't need to listen on 53 only request by recursor DNS authority will dependant to storage (less problematic than recursor)
Decision
Consequences
004 migrate recurson in cluster
Status
done
Context
now that cluster doesn't depend of recursor because request self consul agent for consul query need need to study if we can migrate recursor in nomad wihout break dependance advantage:
- recursor could change client in case of faillure
agains:
- this job need a keepalive IP like pihole
- loss recursor if lost nomad cluster
Decision
put one recursor on cluster over authority server and keep the recursor on gerard for better recundancy
Consequences
005 physical Recursor location
Status
done
Context
following NAS migration physical DNS Recursor was install directly on NAS this bring a SPOF when NAS failed Recursor on Nomad cluster are stopped because of volume dependance
Decision
Put physical Recursor on a cluster node like that to have a DNS issue we need to have NAS and this nomad down on same Time