Red Hat Bugzilla – Bug 1266537
[Doc] Provide more details about DNS requirements
Last modified: 2016-11-08 01:29:19 EST
Section Number and Name:
Prerequites > Environment
Describe the issue:
Provide more details and clarify about DNS requirements. The document still lack of information about it
Suggestions for improvement:
All information needed (or at least most of it) is described in https://access.redhat.com/solutions/1520803
*** Bug 1271400 has been marked as a duplicate of this bug. ***
We should outline that DNS is needed for OpenShift to work fully.
The masterURL needs to be resolvable to the LB or Master so that a pod can resolve the masterURL.
work-in-progress docs: https://github.com/openshift/openshift-docs/pull/2101
made updates, just asking SME questions in BZ:
@rimolive : I understand what you're saying, that blog is for an all-in-one so it has no bearing on enterprise docs. I'm just wondering if there's enough information here for our users to be able to properly configure DNS for a typical cluster (multiple masters and nodes). Am I missing anything in there?
made more updates, asking Ryan Howe for a final tech review, since I incorporated his notes.
Updated again, back to Ryan Howe on something I'm unclear about.
More updates made based on more tech review
Rendered doc for easy reading: http://file.bne.redhat.com/~tpoitras/2016/BZ1266537/openshift-enterprise/dnsreqs-BZ1266537/install_config/install/prerequisites.html#prereq-dns
updated PR based on Tech Review, moving to QA.
See PR comments
Moving along to QE for verification that everything here works.
Attn: Ma Xiaoqiang
in the GitHub PR mentioned above, I have made many updates to the following section regarding DNS configuration:
Please QE test this section for technical accuracy.
Go through the whole DNS section, I did not find any info about how to add master/node DNS record, also not mentioned which kind of DNS server is suggested to use? dnsmsaq installed on node? customized internal bind dns server installed by user? or some office DNS server in user's environment. Most are telling user how to check and validate its DNS configuration. Maybe some user will get confused about why "dig ose3-node1.example.com @172.16.25.41" would result a IP address.
Except the above issue, other part seem good to me.
I'm not sure I understand. I have re-organized the content to make it flow a bit better, but I'm not sure about the things you're mentioning above.
You said: "I did not find any info about how to add master/node DNS record"
Most of this is automated now. "As of OpenShift Enterprise 3.2, dnsmasq is automatically configured on all nodes."
So there's just a couple things to check:
The "Configuring a DNS Environment" shows the process involved: ensure DNS server resolve to all masters & nodes, and if DHCP is enabled, a script takes care of configuration (but you can optionally configure dnsIP in the node-config). If DHCP is disabled, then configure your network interface to be static, and add DNS nameservers to NetworkManager.
You said: "also not mentioned which kind of DNS server is suggested to use? dnsmsaq installed on node? customized internal bind dns server installed by user? or some office DNS server in user's environment."
From the docs: "As of OpenShift Enterprise 3.2, dnsmasq is automatically configured on all nodes."
I'm not sure about the types of DNS servers... do we have data on this anywhere?
You said: "Most are telling user how to check and validate its DNS configuration. Maybe some user will get confused about why "dig ose3-node1.example.com @172.16.25.41" would result a IP address.""
I've hopefully clarified this a bit better.
Please re-check this link for updated docs:
Looks like good to me.
Thanks, Johnny! Moving PR to peer review and moving this BZ to release-pending
PR has merged: https://github.com/openshift/openshift-docs/pull/2101
Once published, will close this BZ.
Doc update published. Closing BZ.