We expect every Nomad API client to use a single connection to any
given agent, so take advantage of keep-alive by switching the default
transport to `DefaultPooledClient`. Provide a facility to close idle
connections for testing purposes.
Restores the previously reverted #12409
Co-authored-by: Ben Buzbee <bbuzbee@cloudflare.com>
The only difference is DefaultTransport sets DisableKeepAlives
This doesn't make much sense to me - every http connection from the
nomad client goes to the same NOMAD_ADDR so it's a great case for keep
alive. Except round robin DNS and anycast perhaps.
Consul does this already
1e47e3c82b/api/api.go (L397)
Move some common Vault API data struct decoding out of the Vault client
so it can be reused in other situations.
Make Vault job validation its own function so it's easier to expand it.
Rename the `Job.VaultPolicies` method to just `Job.Vault` since it
returns the full Vault block, not just their policies.
Set `ChangeMode` on `Vault.Canonicalize`.
Add some missing tests.
Allows specifying an entity alias that will be used by Nomad when
deriving the task Vault token.
An entity alias assigns an indentity to a token, allowing better control
and management of Vault clients since all tokens with the same indentity
alias will now be considered the same client. This helps track Nomad
activity in Vault's audit logs and better control over Vault billing.
Add support for a new Nomad server configuration to define a default
entity alias to be used when deriving Vault tokens. This default value
will be used if the task doesn't have an entity alias defined.
This PR adds support for the raw_exec driver on systems with only cgroups v2.
The raw exec driver is able to use cgroups to manage processes. This happens
only on Linux, when exec_driver is enabled, and the no_cgroups option is not
set. The driver uses the freezer controller to freeze processes of a task,
issue a sigkill, then unfreeze. Previously the implementation assumed cgroups
v1, and now it also supports cgroups v2.
There is a bit of refactoring in this PR, but the fundamental design remains
the same.
Closes#12351#12348
Resolves#12095 by WONTFIXing it.
This approach disables `writeToFile` as it allows arbitrary host
filesystem writes and is only a small quality of life improvement over
multiple `template` stanzas.
This approach has the significant downside of leaving people who have
altered their `template.function_denylist` *still vulnerable!* I added
an upgrade note, but we should have implemented the denylist as a
`map[string]bool` so that new funcs could be denied without overriding
custom configurations.
This PR also includes a bug fix that broke enabling all consul-template
funcs. We repeatedly failed to differentiate between a nil (unset)
denylist and an empty (allow all) one.
Downgrading the Raft version protocol is not a supported operation.
Checking for a downgrade is hard since this information is not stored in
any persistent place. When a server re-joins a cluster with a prior Raft
version, the Serf tag is updated so Nomad can't tell that the version
changed.
Mixed version clusters must be supported to allow for zero-downtime
rolling upgrades. During this it's expected that the cluster will have
mixed Raft versions. Enforcing consistency strong version consistency
would disrupt this flow.
The approach taken here is to store the Raft version on disk. When the
server starts the `raft_protocol` value is written to the file
`data_dir/raft/version`. If that file already exists, its content is
checked against the current `raft_protocol` value to detect downgrades
and prevent the server from starting.
Any other types of errors are ignore to prevent disruptions that are
outside the control of operators. The only option in cases of an invalid
or corrupt file would be to delete it, making this check useless. So
just overwrite its content with the new version and provide guidance on
how to check that their cluster is an expected state.
Pass-through the `-secret` and `-parameter` flags to allow setting
parameters for the snapshot and overriding the secrets we've stored on
the CSI volume in the state store.
This PR introduces support for using Nomad on systems with cgroups v2 [1]
enabled as the cgroups controller mounted on /sys/fs/cgroups. Newer Linux
distros like Ubuntu 21.10 are shipping with cgroups v2 only, causing problems
for Nomad users.
Nomad mostly "just works" with cgroups v2 due to the indirection via libcontainer,
but not so for managing cpuset cgroups. Before, Nomad has been making use of
a feature in v1 where a PID could be a member of more than one cgroup. In v2
this is no longer possible, and so the logic around computing cpuset values
must be modified. When Nomad detects v2, it manages cpuset values in-process,
rather than making use of cgroup heirarchy inheritence via shared/reserved
parents.
Nomad will only activate the v2 logic when it detects cgroups2 is mounted at
/sys/fs/cgroups. This means on systems running in hybrid mode with cgroups2
mounted at /sys/fs/cgroups/unified (as is typical) Nomad will continue to
use the v1 logic, and should operate as before. Systems that do not support
cgroups v2 are also not affected.
When v2 is activated, Nomad will create a parent called nomad.slice (unless
otherwise configured in Client conifg), and create cgroups for tasks using
naming convention <allocID>-<task>.scope. These follow the naming convention
set by systemd and also used by Docker when cgroups v2 is detected.
Client nodes now export a new fingerprint attribute, unique.cgroups.version
which will be set to 'v1' or 'v2' to indicate the cgroups regime in use by
Nomad.
The new cpuset management strategy fixes#11705, where docker tasks that
spawned processes on startup would "leak". In cgroups v2, the PIDs are
started in the cgroup they will always live in, and thus the cause of
the leak is eliminated.
[1] https://www.kernel.org/doc/html/latest/admin-guide/cgroup-v2.htmlCloses#11289Fixes#11705#11773#11933
The go-grpc library used by most CSI plugins doesn't require the
authority header to be set, which violates the HTTP2 spec but doesn't
impact Nomad because both sides of the connection are using the same
library. But plugins written in other languages (`democratic-csi` for
example) may have more strictly conforming gRPC server libraries and
we need to set the authority header manually.
Listing snapshots was incorrectly returning nanoseconds instead of
seconds, and formatting of timestamps both list and create snapshot
was treating the timestamp as though it were nanoseconds instead of
seconds. This resulted in create timestamps always being displayed as
zero values.
Fix the unit conversion error in the command line and the incorrect
extraction in the CSI plugin client code. Beef up the unit tests to
make sure this code is actually exercised.
A volume that has single-use access mode is feasibility checked during
scheduling to ensure that only a single reader or writer claim
exists. However, because feasibility checking is done one alloc at a
time before the plan is written, a job that's misconfigured to have
count > 1 that mounts one of these volumes will pass feasibility
checking.
Enforce the check at validation time instead to prevent us from even
trying to evaluation a job that's misconfigured this way.
When a node is garbage collected, we assume that the volume is no
longer attached to it and ignore the `ErrUnknownNode` error. But we
used `errors.Is` to check for a wrapped error, and RPC flattens the
errors during serialization. This results in an error check that works
in automated testing but not in real clusters. Use a string contains
check instead.
When a node is drained, system jobs are left until last so that
operators can rely on things like log shippers running even as their
applications are getting drained off. Include CSI plugins in this set
so that Controller plugins deployed as services can be handled as
gracefully as Node plugins that are running as system jobs.
The previous output of the `nomad server members` command would output a
column named `Protocol` that displayed the Serf protocol being currently
used by servers.
This is not a configurable option, so it holds very little value to
operators. It is also easy to confuse it with the Raft Protocol version,
which is configurable and highly relevant to operators.
This commit replaces the previous `Protocol` column with the new `Raft
Version`. It also updates the `-detailed` flag to be called `-verbose`
so it matches other commands. The detailed output now also outputs the
same information as the standard output with the addition of the
previous `Protocol` column and `Tags`.
The `related` query param is used to indicate that the request should
return a list of related (next, previous, and blocked) evaluations.
Co-authored-by: Jasmine Dahilig <jasmine@hashicorp.com>
When a Nomad server becomes the Raft leader, it must perform several
actions defined in the establishLeadership function. If any of these
actions fail, Raft will think the node is the leader, but it will not
actually be able to act as a Nomad leader.
In this scenario, leadership must be revoked and transferred to another
server if possible, or the node should retry the establishLeadership
steps.
CSI `CreateVolume` RPC is idempotent given that the topology,
capabilities, and parameters are unchanged. CSI volumes have many
user-defined fields that are immutable once set, and many fields that
are not user-settable.
Update the `Register` RPC so that updating a volume via the API merges
onto any existing volume without touching Nomad-controlled fields,
while validating it with the same strict requirements expected for
idempotent `CreateVolume` RPCs.
Also, clarify that this state store method is used for everything, not just
for the `Register` RPC.
The RPC for listing volume snapshots requires a plugin ID. Update the
`volume snapshot list` command to find the specific plugin from the
provided prefix.
The `CreateSnapshot` RPC expects a plugin ID to be set by the API, but
in the common case of the `nomad volume snapshot create` command, we
don't ask the user for the plugin ID because it's available from the
volume we're snapshotting.
Change the order of the RPC so that we get the volume first and then
use the volume's plugin ID for the plugin if the API didn't set the
value.
The `CSIPlugin.List` RPC was intended to accept a prefix to filter the
list of plugins being listed. This was being accidentally being done
in the state store instead, which contributed to incorrect filtering
behavior for plugins in the `volume plugin status` command.
Move the prefix matching into the RPC so that it calls the
prefix-matching method in the state store if we're looking for a
prefix.
Update the `plugin status command` to accept a prefix for the plugin
ID argument so that it matches the expected behavior of other commands.
When using a prefix value and the * wildcard for namespace, the endpoint
would not take the prefix value into consideration due to the order in
which the checks were executed but also the logic for retrieving volumes
from the state store.
This commit changes the order to check for a prefix first and wraps the
result iterator of the state store query in a filter to apply the
prefix.
The HTTP endpoint for CSI manually serializes the internal struct to
the API struct for purposes of redaction (see also #10470). Add fields
that were missing from this serialization so they don't show up as
always empty in the API response.
The `volume status` command and associated API redacts the entire
mount options instead of just the `MountFlags` field that can contain
sensitive data. Return a redacted value so that the return value makes
sense to operators who have set this field.
