Previously config entries sharing a kind & name but in different
namespaces could occasionally cause "stuck states" in replication
because the namespace fields were ignored during the differential
comparison phase.
Example:
Two config entries written to the primary:
kind=A,name=web,namespace=bar
kind=A,name=web,namespace=foo
Under the covers these both get saved to memdb, so they are sorted by
all 3 components (kind,name,namespace) during natural iteration. This
means that before the replication code does it's own incomplete sort,
the underlying data IS sorted by namespace ascending (bar comes before
foo).
After one pass of replication the primary and secondary datacenters have
the same set of config entries present. If
"kind=A,name=web,namespace=bar" were to be deleted, then things get
weird. Before replication the two sides look like:
primary: [
kind=A,name=web,namespace=foo
]
secondary: [
kind=A,name=web,namespace=bar
kind=A,name=web,namespace=foo
]
The differential comparison phase walks these two lists in sorted order
and first compares "kind=A,name=web,namespace=foo" vs
"kind=A,name=web,namespace=bar" and falsely determines they are the SAME
and are thus cause an update of "kind=A,name=web,namespace=foo". Then it
compares "<nothing>" with "kind=A,name=web,namespace=foo" and falsely
determines that the latter should be DELETED.
During reconciliation the deletes are processed before updates, and so
for a brief moment in the secondary "kind=A,name=web,namespace=foo" is
erroneously deleted and then immediately restored.
Unfortunately after this replication phase the final state is identical
to the initial state, so when it loops around again (rate limited) it
repeats the same set of operations indefinitely.
Whenever an upsert/deletion of a config entry happens, within the open
state store transaction we speculatively test compile all discovery
chains that may be affected by the pending modification to verify that
the write would not create an erroneous scenario (such as splitting
traffic to a subset that did not exist).
If a single discovery chain evaluation references two config entries
with the same kind and name in different namespaces then sometimes the
upsert/deletion would be falsely rejected. It does not appear as though
this bug would've let invalid writes through to the state store so the
correction does not require a cleanup phase.
Lots of constants were added for various tags that would concern users and are not already parsed out.
Additionally two methods on the AgentMember type were added to ask a member what its ACL Mode is and whether its a server or not.
During gossip encryption key rotation it would be nice to be able to see if all nodes are using the same key. This PR adds another field to the json response from `GET v1/operator/keyring` which lists the primary keys in use per dc. That way an operator can tell when a key was successfully setup as primary key.
Based on https://github.com/hashicorp/serf/pull/611 to add primary key to list keyring output:
```json
[
{
"WAN": true,
"Datacenter": "dc2",
"Segment": "",
"Keys": {
"0OuM4oC3Os18OblWiBbZUaHA7Hk+tNs/6nhNYtaNduM=": 6,
"SINm887hKTzmMWeBNKTJReaTLX3mBEJKriDyt88Ad+g=": 6
},
"PrimaryKeys": {
"SINm887hKTzmMWeBNKTJReaTLX3mBEJKriDyt88Ad+g=": 6
},
"NumNodes": 6
},
{
"WAN": false,
"Datacenter": "dc2",
"Segment": "",
"Keys": {
"0OuM4oC3Os18OblWiBbZUaHA7Hk+tNs/6nhNYtaNduM=": 8,
"SINm887hKTzmMWeBNKTJReaTLX3mBEJKriDyt88Ad+g=": 8
},
"PrimaryKeys": {
"SINm887hKTzmMWeBNKTJReaTLX3mBEJKriDyt88Ad+g=": 8
},
"NumNodes": 8
},
{
"WAN": false,
"Datacenter": "dc1",
"Segment": "",
"Keys": {
"0OuM4oC3Os18OblWiBbZUaHA7Hk+tNs/6nhNYtaNduM=": 3,
"SINm887hKTzmMWeBNKTJReaTLX3mBEJKriDyt88Ad+g=": 8
},
"PrimaryKeys": {
"SINm887hKTzmMWeBNKTJReaTLX3mBEJKriDyt88Ad+g=": 8
},
"NumNodes": 8
}
]
```
I intentionally did not change the CLI output because I didn't find a good way of displaying this information. There are a couple of options that we could implement later:
* add a flag to show the primary keys
* add a flag to show json output
Fixes#3393.
Issue and PR numbers do not overlap, they are based of the same counter.
A PR can be also linked to via issues, if it is a PR, Github will
redirect to it.
This change has the benefit that one can link to both - issues and PRs.
Mike Morris
R.B. Boyer
Daniel Nephin
Kyle Havlovitz
Hans Hasselberg
Matt Keeler
Tim Arenz
Seth Hoenig
Jack