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Typo fixes, grammar, style in DNS Debugging (#19961)

pull/19999/head
nfd (aka alex) 2020-03-29 22:07:53 -07:00 committed by bryan
parent 0624e8799b
commit 3adff70277
1 changed files with 3 additions and 3 deletions
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content/en/docs/tasks/administer-cluster/dns-debugging-resolution.md
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@ -248,7 +248,7 @@ linux/amd64, go1.10.3, 2e322f6
## Known issues
Some Linux distributions (e.g. Ubuntu), use a local DNS resolver by default (systemd-resolved).
Some Linux distributions (e.g. Ubuntu) use a local DNS resolver by default (systemd-resolved).
Systemd-resolved moves and replaces `/etc/resolv.conf` with a stub file that can cause a fatal forwarding
loop when resolving names in upstream servers. This can be fixed manually by using kubelet's `--resolv-conf` flag
to point to the correct `resolv.conf` (With `systemd-resolved`, this is `/run/systemd/resolve/resolv.conf`).
@ -258,10 +258,10 @@ Kubernetes installs do not configure the nodes' `resolv.conf` files to use the
cluster DNS by default, because that process is inherently distribution-specific.
This should probably be implemented eventually.
Linux's libc (a.k.a. glibc) has a limit for the DNS `nameserver` records to 3 by default. What's more, for the glibc versions which are older than glic-2.17-222 ([the new versions update see this issue](https://access.redhat.com/solutions/58028)), the DNS `search` records has been limited to 6 ([see this bug from 2005](https://bugzilla.redhat.com/show_bug.cgi?id=168253)). Kubernetes needs to consume 1 `nameserver` record and 3 `search` records. This means that if a local installation already uses 3 `nameserver`s or uses more than 3 `search`es while your glibc versions in the affected list, some of those settings will be lost. For the workaround of the DNS `nameserver` records limit, the node can run `dnsmasq` which will provide more `nameserver` entries, you can also use kubelet's `--resolv-conf` flag. For fixing the DNS `search` records limit, consider upgrading your linux distribution or glibc version.
Linux's libc (a.k.a. glibc) has a limit for the DNS `nameserver` records to 3 by default. What's more, for the glibc versions which are older than glibc-2.17-222 ([the new versions update see this issue](https://access.redhat.com/solutions/58028)), the allowed number of DNS `search` records has been limited to 6 ([see this bug from 2005](https://bugzilla.redhat.com/show_bug.cgi?id=168253)). Kubernetes needs to consume 1 `nameserver` record and 3 `search` records. This means that if a local installation already uses 3 `nameserver`s or uses more than 3 `search`es while your glibc version is in the affected list, some of those settings will be lost. To work around the DNS `nameserver` records limit, the node can run `dnsmasq`, which will provide more `nameserver` entries. You can also use kubelet's `--resolv-conf` flag. To fix the DNS `search` records limit, consider upgrading your linux distribution or upgrading to an unaffected version of glibc.
If you are using Alpine version 3.3 or earlier as your base image, DNS may not
work properly owing to a known issue with Alpine.
work properly due to a known issue with Alpine.
Check [here](https://github.com/kubernetes/kubernetes/issues/30215)
for more information.