Commit graph

68 commits

Author SHA1 Message Date
Alexander Block
89e570493a Also add the system nameservers to upstream servers in dnsmasq
Also make no-resolv unconditional again. Otherwise, we may end up in
a resolver loop. The resolver loop was the cause for the piling up
parallel queries.
2017-02-08 14:38:55 +01:00
Matthew Mosesohn
fd30131dc2 Revert "Drop linux capabilities and rework users/groups" 2017-02-06 15:58:54 +03:00
Bogdan Dobrelya
cae2982d81 Merge pull request #911 from bogdando/DROP_CAPS
Drop linux capabilities and rework users/groups
2017-02-06 12:05:51 +01:00
Artem Panchenko
1418fb394b Explicitly set config path for DNSMasq
When DNSMasq is configured to read its settings
from a folder ('-7' or '--conf-dir' option) it only
checks that the directory exists and doesn't fail if
it's empty. It could lead to a situation when DNSMasq
is running and handles requests, but not properly
configured, so some of queries can't be resolved.
2017-01-31 12:14:57 +02:00
Brad Beam
b54eb609bf Consolidating kube.py module 2017-01-27 11:28:11 -06:00
Bogdan Dobrelya
cb2e5ac776 Drop linux capabilities and rework users/groups
* Drop linux capabilities for unprivileged containerized
  worlkoads Kargo configures for deployments.
* Configure required securityContext/user/group/groups for kube
  components' static manifests, etcd, calico-rr and k8s apps,
  like dnsmasq daemonset.
* Rework cloud-init (etcd) users creation for CoreOS.
* Fix nologin paths, adjust defaults for addusers role and ensure
  supplementary groups membership added for users.
* Add netplug user for network plugins (yet unused by privileged
  networking containers though).
* Grant the kube and netplug users read access for etcd certs via
  the etcd certs group.
* Grant group read access to kube certs via the kube cert group.
* Remove priveleged mode for calico-rr and run it under its uid/gid
  and supplementary etcd_cert group.
* Adjust docs.
* Align cpu/memory limits and dropped caps with added rkt support
  for control plane.

Signed-off-by: Bogdan Dobrelya <bogdando@mail.ru>
2017-01-20 08:50:42 +01:00
Sergii Golovatiuk
61d05dea58 Allow to specify number of concurrent DNS queries
ndots creates overhead as every pod creates 5 concurrent connections
that are forwarded to sky dns. Under some circumstances dnsmasq may
prevent forwarding traffic with "Maximum number of concurrent DNS
queries reached" in the logs.

This patch allows to configure the number of concurrent forwarded DNS
queries "dns-forward-max" as well as "cache-size" leaving the default
values as they were before.

Signed-off-by: Sergii Golovatiuk <sgolovatiuk@mirantis.com>
2017-01-19 11:47:37 +01:00
Alexander Block
a8b5b856d1 Only use default resolver in dnsmasq when we are using host_resolvconf mode 2017-01-06 10:21:07 +01:00
Alexander Block
1d2a18b355 Introduce dns_mode and resolvconf_mode and implement docker_dns mode
Also update reset.yml to do more dns/network related cleanup.
2017-01-05 23:38:51 +01:00
Bogdan Dobrelya
bb0c3537cb Do not forward bogus domains for upstream resolvers
Also fix kube log level 4 to log dnsmasq queries.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
2016-12-23 11:53:14 +01:00
Bogdan Dobrelya
f10d1327d4 Revert "Do not forward private domains for upstream resolvers" 2016-12-21 15:24:17 +01:00
Bogdan Dobrelya
101864c050 Do not forward private domains for upstream resolvers
Also fix kube log level 4 to log dnsmasq queries.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
Co-authored-by: Matthew Mosesohn <mmosesohn@mirantis.com>
2016-12-19 11:01:41 +01:00
Bogdan Dobrelya
c75f394707 Address standalone kubelet config case
Also place in global vars and do not repeat the kube_*_config_dir
and kube_namespace vars for better code maintainability and UX.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
2016-12-13 16:35:53 +01:00
Bogdan Dobrelya
a15d626771 Preconfigure DNS stack and docker early
In order to enable offline/intranet installation cases:
* Move DNS/resolvconf configuration to preinstall role. Remove
  skip_dnsmasq_k8s var as not needed anymore.

* Preconfigure DNS stack early, which may be the case when downloading
  artifacts from intranet repositories. Do not configure
  K8s DNS resolvers for hosts /etc/resolv.conf yet early (as they may be
  not existing).

* Reconfigure K8s DNS resolvers for hosts only after kubedns/dnsmasq
  was set up and before K8s apps to be created.

* Move docker install task to early stage as well and unbind it from the
  etcd role's specific install path. Fix external flannel dependency on
  docker role handlers. Also fix the docker restart handlers' steps
  ordering to match the expected sequence (the socket then the service).

* Add default resolver fact, which is
  the cloud provider specific and remove hardcoded GCE resolver.

* Reduce default ndots for hosts /etc/resolv.conf to 2. Multiple search
  domains combined with high ndots values lead to poor performance of
  DNS stack and make ansible workers to fail very often with the
  "Timeout (12s) waiting for privilege escalation prompt:" error.

* Update docs.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
2016-12-09 17:30:55 +01:00
Bogdan Dobrelya
8cc84e132a Add tags
Add tags to allow more granular tasks filtering.
Add generator script for MD formatted tags found.
Add docs for tags how-to.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
2016-12-09 12:14:28 +01:00
Antoine Legrand
5b382668f5 Merge pull request #529 from bogdando/netcheck
Add a k8s app for advanced e2e netcheck for DNS
2016-11-28 15:26:30 +01:00
Bogdan Dobrelya
b7692fad09 Add advanced net check for DNS K8s app
* Add an option to deploy K8s app to test e2e network connectivity
  and cluster DNS resolve via Kubedns for nethost/simple pods
  (defaults to false).
* Parametrize existing k8s apps templates with kube_namespace and
  kube_config_dir instead of hardcode.
* For CoreOS, ensure nameservers from inventory to be put in the
  first place to allow hostnet pods connectivity via short names
  or FQDN and hostnet agents to pass as well, if netchecker
  deployed.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
2016-11-28 13:23:25 +01:00
Bogdan Dobrelya
2d18e19263 Tune dnsmasq/kubedns limits, replicas, logging
* Add dns_replicas, dns_memory/cpu_limit/requests vars for
dns related apps.
* When kube_log_level=4, log dnsmasq queries as well.
* Add log level control for skydns (part of kubedns app).
* Add limits/requests vars for dnsmasq (part of kubedns app) and
  dnsmasq daemon set.
* Drop string defaults for kube_log_level as it is int and
  is defined in the global vars as well.
* Add docs

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
2016-11-25 12:49:17 +01:00
Bogdan Dobrelya
aa447585c4 Fix download dnsmasq image dependency on docker
When download_run_once with download_localhost is used, docker is
expected to be running on the delegate localhost. That may be not
the case for a non localhost delegate, which is the kube-master
otherwise. Then the dnsmasq role, had it been invoked early before
deployment starts, would fail because of the missing docker dependency.

* Fix that dependency on docker and do not pre download dnsmasq image
  for the dnsmasq role, if download_localhost is disabled.
* Remove become: false for docker CLI invocation because that's not
  the common pattern to allow users access docker CLI w/o sudo.
* Fix opt bin path hack for localhost delegate to ignore errors when
  it fails with "sudo password required" otherwise.
* Describe download_run_once with download_localhost use case in docs
  as well.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
2016-11-24 18:31:26 +01:00
Bogdan Dobrelya
d208896c46 Ensure /etc/resolv.conf content for CoreOS
Use cloud-init config to replace /etc/resolv.conf with the
content for kubelet to properly configure hostnet pods.

Do not use systemd-resolved yet, see
https://coreos.com/os/docs/latest/configuring-dns.html
"Only nss-aware applications can take advantage of the
systemd-resolved cache. Notably, this means that statically
linked Go programs and programs running within Docker/rkt
will use /etc/resolv.conf only, and will not use the
systemd-resolve cache."

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
2016-11-23 16:51:49 +01:00
Bogdan Dobrelya
dff78f616e Allow pre-downloaded images to be used effectively
According to http://kubernetes.io/docs/user-guide/images/ :
By default, the kubelet will try to pull each image from the
specified registry. However, if the imagePullPolicy property
of the container is set to IfNotPresent or Never, then a local\
image is used (preferentially or exclusively, respectively).

Use IfNotPresent value to allow images prepared by the download
role dependencies to be effectively used by kubelet without pull
errors resulting apps to stay blocked in PullBackOff/Error state
even when there are images on the localhost exist.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
2016-11-22 16:16:04 +01:00
Bogdan Dobrelya
66f27ed1f3 Download images as dependencies of roles
Pre download all required container images as roles' deps.
Drop unused flannel-server-helper images pre download.
Improve pods creation post-install test pre downloaded busybox.
Improve logs collection script with kubectl describe, fix sudo/etcd/weave
commands.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
2016-11-22 11:13:57 +01:00
Matthew Mosesohn
d8b06f3e2f Ignore changes on check resolvconf task 2016-10-28 10:38:16 +04:00
Matthew Mosesohn
2778ac61a4 Add new var skip_dnsmasq_k8s
If skip_dnsmasq is set, it will still not set up dnsmasq
k8s pod. This enables independent setup of resolvconf section
before kubelet is up.
2016-10-26 17:56:15 +03:00
Matthew Mosesohn
4b7347f1cd fix dnsmasq template cloud_provider lookup 2016-10-21 13:00:40 +03:00
Chad Swenson
c402feffbd Parameterize several dependency endpoints so that they can be overridden with internal mirrors.
Signed-off-by: Chad Swenson <chadswen@gmail.com>
2016-10-15 12:26:52 -05:00
Smana
056f4b6c00 upgrade to kubernetes version 1.4.0
test to change the machine type

Revert "test to change the machine type"

This reverts commit 7a91f1b5405a39bee6cb91940b09a0b0f9d3aee1.

use google dns server when no upstream dns are defined

comment upstream_dns_servers

update documentation

remove deprecated kubelet flags

Revert "remove deprecated kubelet flags"

This reverts commit 21e3b893c896d0291c36a07d0414f4cb88b8d8ac.
2016-10-10 22:44:47 +02:00
Matthew Mosesohn
5579cddbdb Disable reverse lookups again
Initially this was removed, but it turns out that services that
perform reverse lookups (such as MariaDB) will encounter severe
performance degredation with this disabled.
2016-09-29 10:49:55 +04:00
Bogdan Dobrelya
5fd43b7cf0 Allow subdomains of dns_domain and fix kubelet restarts
* Add a var for ndots (default 5) and put it hosts' /etc/resolv.conf.
* Poke kube dns container image to v1.7
* In order to apply changes to kubelet, notify it to
be restarted on changes made to /etc/resolv.conf. Ignore errors as the kubelet
may yet to be present up to the moment of the notification being processed.
* Remove unnecessary kubelet restart for master role as the node role ensures
it is up and running. Notify master static pods waiters for apiserver,
scheduler, controller-manager instead.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
2016-09-27 14:32:49 +02:00
Bogdan Dobrelya
dfb9063b3f Fix docs and dns servers placement order
- Update docs and a drawing to clarify DNS setup.
- Change order of nameservers placement to match
  changes in https://github.com/kubespray/kargo/pull/501

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
2016-09-23 16:16:00 +02:00
Bogdan Dobrelya
82ee60fe8b Make dnsmasq daemon set optional
Change additional dnsmasq opts:
- Adjust caching size and TTL
- Disable resolve conf to not create loops
- Change dnsPolicy to default (similarly to kubedns's dnsmasq). The
  ClusterFirst should not be used to not create loops
- Disable negative NXDOMAIN replies to be cached
- Make its very installation as optional step (enabled by default).
  If you don't want more than 3 DNS servers, including 1 for K8s, disable
  it.
- Add docs and a drawing to clarify DNS setup.
- Fix stdout logs for dnsmasq/kubedns app configs
- Add missed notifies to resolvconf -u handler
- Fix idempotency of resolvconf head file changes

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
2016-09-23 12:59:06 +02:00
Matthew Mosesohn
d313be4420 Improve management of nameservers in resolv.conf
Changing nameservers now will clean up previous entries
2016-09-22 18:11:15 +03:00
Özgür Caner
123532d2a4 Changed ImagePullPolicy from Always to IfNotPresent to avoid download issue when DNS is not working 2016-09-20 10:34:44 +02:00
Ivan Shvedunov
13874f4610 Fix reverse DNS lookups of service IPs.
This fixes "DNS should provide DNS for services [Conformance]"
e2e test in k8s.
2016-09-19 09:12:10 +03:00
Matthew Mosesohn
ef43b21597 Fix kubedns idempotency
Removed api-version from kube.py because it is deprecated.
Updating both kube.py because dnsmasq one is actually used.
Fixed name back to kubedns for checking its resource.
2016-09-13 16:49:51 +03:00
Bogdan Dobrelya
d240073f65 Fix updating resolvconf
Move updating resolvconf to the network restart handler to
ensure changes applied to the /etc/resolv.conf.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
2016-09-01 11:10:26 +02:00
Matthew Mosesohn
33c8d0a1a7 Remove search and nameserver entries from resolvconf base
These items conflict when they are provided also in head file
Fixes: #456
2016-08-30 13:14:44 +03:00
Bogdan Dobrelya
ea57ce7514 Fix resolv.conf search/nameserver
* Ensure additional nameserver/search, if defined as vars.
* Don't backup changed dhclient hooks as they are going to be
  executed by dhclient as well, which is not what we want.
* For debian OS family only:
- Rename nodnsupdate hook the resolvconf hook to be sourced always
before it.
- Ensure dhclient restarted via network restart to apply the
nodnsupdate hook.
* For rhel OS family, the fix TBD, it doesn't work the same way.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
2016-08-24 15:31:57 +02:00
Smana
643b28f9d3 Revert "Fix resolv.conf search/nameserver"
This reverts commit 977f82c32c.
2016-08-24 12:36:25 +02:00
Bogdan Dobrelya
977f82c32c Fix resolv.conf search/nameserver
Rename nodnsupdate hook the resolvconf hook to be sourced always
before it.
Ensure dhclient restarted via network restart to apply the
nodnsupdate hook.
Ensure additional nameserver/search, if defined as vars.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
2016-08-22 11:53:44 +02:00
dis
0fa90ec9e8 Fix resolvconf executable discovery
If resolvconf was installed and then removed, the file
/etc/resolvconf/resolv.conf.d/head remains in the filesystem

- change discovery of 'resolvconf' executable to check if it
  can be located with 'which resolvconf' command or not.
2016-08-10 17:22:33 +03:00
Matthew Mosesohn
acae5d4286 Check dnsmasq on first kube-node
kube-masters without kube-node role will not run
kube-proxy, and therefore can't check if dnsmasq
is running.

Fixes #368
2016-08-05 16:55:48 +04:00
Stig Telfer
64a39fdb86 Use var for bin dir instead of assuming /usr/local/bin
On CoreOS the binaries are not installed in /usr/local/bin.
2016-04-02 20:53:33 +01:00
teuto.net Netzdienste GmbH
457ed11b49 fixed deprecation warnings regarding bare variables 2016-03-30 10:23:43 +02:00
Smaine Kahlouch
7e6d7caf4b Dnsmasq runs on all nodes 2016-03-21 11:37:35 +01:00
ant31
6297e5ea93 Use dnsmasq inside pods 2016-03-19 23:41:27 +01:00
Antoine Legrand
b9781fa7c2 Symlink dnsmasq conf 2016-01-26 00:30:29 +01:00
Smaine Kahlouch
a5094f2a6a move /etc/hosts configuration in 'preinstall' role 2016-01-20 17:37:23 +01:00
Greg Althaus
fe5ec398bf Use IP is specified, otherwise use the ansible discovered address.
This fixes cases for use in Vagrant environments.
2016-01-20 08:34:39 -06:00
Smaine Kahlouch
b54af6b42f reduce dns timeout 2016-01-19 13:49:33 +01:00