When using
dns_upstream_forward_extra_opts:
prefer_udp: "" # the option as no value so use empty string to just
# put the key
This is rendered in the dns configmap as ($ for end-of-line)
...
prefer_udp $
...
Note the trailing space.
This triggers https://github.com/kubernetes/kubernetes/issues/36222,
which makes the configmap hardly readable when editing them manually or
simply putting them in a yaml file for inspection.
Trim the concatenation of option + value to get rid of any trailing
space.
Handle all old dns domains:
- for nodelocaldns: in the same server block as the current dns_domain
- for coredns: uffix rewrite of each of the old dns domains to the
current one
8080 is a pretty common port, using nodelocaldns_ip:8080 still
prevents node processes or hostNetwork=true processes to bind to *:8080
so switch to 9254 by default (prometheus port is 9253)
Signed-off-by: Etienne Champetier <champetier.etienne@gmail.com>
* Set cluster DNS correctly in case of nodelocal dns cache
* Pass in cluster_ip based on dns mode
* Disable nodelocaldns by default
* Fix syntax error
* Fix syntax issue
* Add nodelocadns ip to vars of node installation
* Change location of nodelocaldns_ip
* Try to remove newlines from jinja template
* Add debug for config file
* Move parameter logic outside of template
* Adapt templates after feedback
* Remove debugging
* Add support for running a nodelocal dns cache
After encountering dns issues in a cluster I was recently working on I
noticed Kubernetes 1.13 introduced support for running a nodelocal dns
cache.
I believe this can usefull for more people.
73b548db06https://github.com/kubernetes/enhancements/blob/master/keps/sig-network/0030-nodelocal-dns-cache.md
* Add requested changes
* Add additional requested changes + documentation
* Add requested changes after review
* Replace incorrect variable
