Bug 2017564: Prepend to search domains instead of replacing #2823
Conversation
Previously the resolv-prepender script overwrote the search domains with a specific set of domains, notably including the cluster domain so cluster addresses will resolve. However, this is not desirable as it may miss some configured search domains if they don't happen to come in via DHCP (for example, search domains configured on an interface via nmcli/nmstate). This change modifies the prepender logic to also prepend the cluster domain to the search domain list rather than overwrite it completely. This means that we don't have to manage the full list of search domains like we did before. We just add on to the default ones NetworkManager writes, which should result in less confusing DNS behavior from the script. One caveat is that I don't know if the same method can be used for the resolved case and I don't have any way to test that locally, so I've left the logic there alone for now. If this turns out to be a problem for OKD as well then someone will have to work with us to get that behavior changed too.
|
/hold I need to test this locally to make sure I didn't miss any changes when I templated the new commands. |
openshift-ci
bot
added
the
do-not-merge/hold
cybertron
changed the title
openshift-ci
bot
added
the
bugzilla/severity-urgent
|
@cybertron: This pull request references Bugzilla bug 2017564, which is valid. The bug has been moved to the POST state. The bug has been updated to refer to the pull request using the external bug tracker. 3 validation(s) were run on this bug
No GitHub users were found matching the public email listed for the QA contact in Bugzilla (vvoronko@redhat.com), skipping review request. In response to this:
Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository. |
openshift-ci
bot
added
the
bugzilla/valid-bug
|
/hold cancel Results from my local test run: And with a custom search domain and server added: Everything seems to be working as intended. Except that GitHub formatting is eating the "Generated by" comment. :-) |
openshift-ci
bot
removed
the
do-not-merge/hold
|
/retest-required |
1 similar comment
|
/retest-required |
openshift-ci
bot
requested review from
jcpowermac,
mandre,
patrickdillon and
rvanderp3
|
/test e2e-vsphere |
|
/retest-required |
|
@rvanderp3 e2e-vsphere is pretty red but e2e-vsphere-upgrade is passing should we be waiting for a green run on that? |
|
/retest-required |
|
/lgtm |
|
[APPROVALNOTIFIER] This PR is APPROVED This pull-request has been approved by: cybertron, jcpowermac, kikisdeliveryservice, mandre The full list of commands accepted by this bot can be found here. The pull request process is described here
Needs approval from an approver in each of these files:
Approvers can indicate their approval by writing |
openshift-ci
bot
added
the
approved
|
/retest-required Please review the full test history for this PR and help us cut down flakes. |
3 similar comments
|
/retest-required Please review the full test history for this PR and help us cut down flakes. |
|
/retest-required Please review the full test history for this PR and help us cut down flakes. |
|
/retest-required Please review the full test history for this PR and help us cut down flakes. |
|
@cybertron: The following tests failed, say
Full PR test history. Your PR dashboard. Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository. I understand the commands that are listed here. |
|
/retest-required Please review the full test history for this PR and help us cut down flakes. |
8 similar comments
|
/retest-required Please review the full test history for this PR and help us cut down flakes. |
|
/retest-required Please review the full test history for this PR and help us cut down flakes. |
|
/retest-required Please review the full test history for this PR and help us cut down flakes. |
|
/retest-required Please review the full test history for this PR and help us cut down flakes. |
|
/retest-required Please review the full test history for this PR and help us cut down flakes. |
|
/retest-required Please review the full test history for this PR and help us cut down flakes. |
|
/retest-required Please review the full test history for this PR and help us cut down flakes. |
|
/retest-required Please review the full test history for this PR and help us cut down flakes. |
|
@cybertron: All pull requests linked via external trackers have merged: Bugzilla bug 2017564 has been moved to the MODIFIED state. In response to this:
Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository. |
|
/cherry-pick release-4.9 |
|
@creydr: new pull request created: #2965 In response to this:
Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository. |
Previously the resolv-prepender script overwrote the search domains
with a specific set of domains, notably including the cluster domain
so cluster addresses will resolve. However, this is not desirable as
it may miss some configured search domains if they don't happen to
come in via DHCP (for example, search domains configured on an
interface via nmcli/nmstate).
This change modifies the prepender logic to also prepend the cluster
domain to the search domain list rather than overwrite it completely.
This means that we don't have to manage the full list of search
domains like we did before. We just add on to the default ones
NetworkManager writes, which should result in less confusing DNS
behavior from the script.
One caveat is that I don't know if the same method can be used for
the resolved case and I don't have any way to test that locally, so
I've left the logic there alone for now. If this turns out to be a
problem for OKD as well then someone will have to work with us to
get that behavior changed too.
- What I did
- How to verify it
- Description for the changelog
The resolv-prepender script no longer overwrites the search domain list. Instead, it prepends the cluster domain so cluster addresses will resolve as expected, but any custom DNS settings will also be respected.