consul

Branch: add-docs-for-anno

Commit Graph

Author	SHA1	Message	Date
R.B. Boyer	77f2e54618	create lib/stringslice package (#7934 )	5 years ago
R.B. Boyer	ddd0a13e27	agent: handle re-bootstrapping in a secondary datacenter when WAN federation via mesh gateways is configured (#7931 ) The main fix here is to always union the `primary-gateways` list with the list of mesh gateways in the primary returned from the replicated federation states list. This will allow any replicated (incorrect) state to be supplemented with user-configured (correct) state in the config file. Eventually the game of random selection whack-a-mole will pick a winning entry and re-replicate the latest federation states from the primary. If the user-configured state is actually the incorrect one, then the same eventual correct selection process will work in that case, too. The secondary fix is actually to finish making wanfed-via-mgws actually work as originally designed. Once a secondary datacenter has replicated federation states for the primary AND managed to stand up its own local mesh gateways then all of the RPCs from a secondary to the primary SHOULD go through two sets of mesh gateways to arrive in the consul servers in the primary (one hop for the secondary datacenter's mesh gateway, and one hop through the primary datacenter's mesh gateway). This was neglected in the initial implementation. While everything works, ideally we should treat communications that go around the mesh gateways as just provided for bootstrapping purposes. Now we heuristically use the success/failure history of the federation state replicator goroutine loop to determine if our current mesh gateway route is working as intended. If it is, we try using the local gateways, and if those don't work we fall back on trying the primary via the union of the replicated state and the go-discover configuration flags. This can be improved slightly in the future by possibly initializing the gateway choice to local on startup if we already have replicated state. This PR does not address that improvement. Fixes #7339	5 years ago
R.B. Boyer	6adad71125	wan federation via mesh gateways (#6884 ) This is like a Möbius strip of code due to the fact that low-level components (serf/memberlist) are connected to high-level components (the catalog and mesh-gateways) in a twisty maze of references which make it hard to dive into. With that in mind here's a high level summary of what you'll find in the patch: There are several distinct chunks of code that are affected: * new flags and config options for the server * retry join WAN is slightly different * retry join code is shared to discover primary mesh gateways from secondary datacenters * because retry join logic runs in the agent and the results of that operation for primary mesh gateways are needed in the server there are some methods like `RefreshPrimaryGatewayFallbackAddresses` that must occur at multiple layers of abstraction just to pass the data down to the right layer. * new cache type `FederationStateListMeshGatewaysName` for use in `proxycfg/xds` layers * the function signature for RPC dialing picked up a new required field (the node name of the destination) * several new RPCs for manipulating a FederationState object: `FederationState:{Apply,Get,List,ListMeshGateways}` * 3 read-only internal APIs for debugging use to invoke those RPCs from curl * raft and fsm changes to persist these FederationStates * replication for FederationStates as they are canonically stored in the Primary and replicated to the Secondaries. * a special derivative of anti-entropy that runs in secondaries to snapshot their local mesh gateway `CheckServiceNodes` and sync them into their upstream FederationState in the primary (this works in conjunction with the replication to distribute addresses for all mesh gateways in all DCs to all other DCs) * a "gateway locator" convenience object to make use of this data to choose the addresses of gateways to use for any given RPC or gossip operation to a remote DC. This gets data from the "retry join" logic in the agent and also directly calls into the FSM. * RPC (`:8300`) on the server sniffs the first byte of a new connection to determine if it's actually doing native TLS. If so it checks the ALPN header for protocol determination (just like how the existing system uses the type-byte marker). * 2 new kinds of protocols are exclusively decoded via this native TLS mechanism: one for ferrying "packet" operations (udp-like) from the gossip layer and one for "stream" operations (tcp-like). The packet operations re-use sockets (using length-prefixing) to cut down on TLS re-negotiation overhead. * the server instances specially wrap the `memberlist.NetTransport` when running with gateway federation enabled (in a `wanfed.Transport`). The general gist is that if it tries to dial a node in the SAME datacenter (deduced by looking at the suffix of the node name) there is no change. If dialing a DIFFERENT datacenter it is wrapped up in a TLS+ALPN blob and sent through some mesh gateways to eventually end up in a server's :8300 port. * a new flag when launching a mesh gateway via `consul connect envoy` to indicate that the servers are to be exposed. This sets a special service meta when registering the gateway into the catalog. * `proxycfg/xds` notice this metadata blob to activate additional watches for the FederationState objects as well as the location of all of the consul servers in that datacenter. * `xds:` if the extra metadata is in place additional clusters are defined in a DC to bulk sink all traffic to another DC's gateways. For the current datacenter we listen on a wildcard name (`server.<dc>.consul`) that load balances all servers as well as one mini-cluster per node (`<node>.server.<dc>.consul`) * the `consul tls cert create` command got a new flag (`-node`) to help create an additional SAN in certs that can be used with this flavor of federation.	5 years ago

Author

SHA1

Message

Date

R.B. Boyer

77f2e54618

create lib/stringslice package (#7934 )

5 years ago

R.B. Boyer

ddd0a13e27

agent: handle re-bootstrapping in a secondary datacenter when WAN federation via mesh gateways is configured (#7931 )

The main fix here is to always union the `primary-gateways` list with
the list of mesh gateways in the primary returned from the replicated
federation states list. This will allow any replicated (incorrect) state
to be supplemented with user-configured (correct) state in the config
file. Eventually the game of random selection whack-a-mole will pick a
winning entry and re-replicate the latest federation states from the
primary. If the user-configured state is actually the incorrect one,
then the same eventual correct selection process will work in that case,
too.

The secondary fix is actually to finish making wanfed-via-mgws actually
work as originally designed. Once a secondary datacenter has replicated
federation states for the primary AND managed to stand up its own local
mesh gateways then all of the RPCs from a secondary to the primary
SHOULD go through two sets of mesh gateways to arrive in the consul
servers in the primary (one hop for the secondary datacenter's mesh
gateway, and one hop through the primary datacenter's mesh gateway).
This was neglected in the initial implementation. While everything
works, ideally we should treat communications that go around the mesh
gateways as just provided for bootstrapping purposes.

Now we heuristically use the success/failure history of the federation
state replicator goroutine loop to determine if our current mesh gateway
route is working as intended. If it is, we try using the local gateways,
and if those don't work we fall back on trying the primary via the union
of the replicated state and the go-discover configuration flags.

This can be improved slightly in the future by possibly initializing the
gateway choice to local on startup if we already have replicated state.
This PR does not address that improvement.

Fixes #7339

5 years ago

R.B. Boyer

6adad71125

wan federation via mesh gateways (#6884 )

This is like a Möbius strip of code due to the fact that low-level components (serf/memberlist) are connected to high-level components (the catalog and mesh-gateways) in a twisty maze of references which make it hard to dive into. With that in mind here's a high level summary of what you'll find in the patch:

There are several distinct chunks of code that are affected:

* new flags and config options for the server

* retry join WAN is slightly different

* retry join code is shared to discover primary mesh gateways from secondary datacenters

* because retry join logic runs in the *agent* and the results of that
  operation for primary mesh gateways are needed in the *server* there are
  some methods like `RefreshPrimaryGatewayFallbackAddresses` that must occur
  at multiple layers of abstraction just to pass the data down to the right
  layer.

* new cache type `FederationStateListMeshGatewaysName` for use in `proxycfg/xds` layers

* the function signature for RPC dialing picked up a new required field (the
  node name of the destination)

* several new RPCs for manipulating a FederationState object:
  `FederationState:{Apply,Get,List,ListMeshGateways}`

* 3 read-only internal APIs for debugging use to invoke those RPCs from curl

* raft and fsm changes to persist these FederationStates

* replication for FederationStates as they are canonically stored in the
  Primary and replicated to the Secondaries.

* a special derivative of anti-entropy that runs in secondaries to snapshot
  their local mesh gateway `CheckServiceNodes` and sync them into their upstream
  FederationState in the primary (this works in conjunction with the
  replication to distribute addresses for all mesh gateways in all DCs to all
  other DCs)

* a "gateway locator" convenience object to make use of this data to choose
  the addresses of gateways to use for any given RPC or gossip operation to a
  remote DC. This gets data from the "retry join" logic in the agent and also
  directly calls into the FSM.

* RPC (`:8300`) on the server sniffs the first byte of a new connection to
  determine if it's actually doing native TLS. If so it checks the ALPN header
  for protocol determination (just like how the existing system uses the
  type-byte marker).

* 2 new kinds of protocols are exclusively decoded via this native TLS
  mechanism: one for ferrying "packet" operations (udp-like) from the gossip
  layer and one for "stream" operations (tcp-like). The packet operations
  re-use sockets (using length-prefixing) to cut down on TLS re-negotiation
  overhead.

* the server instances specially wrap the `memberlist.NetTransport` when running
  with gateway federation enabled (in a `wanfed.Transport`). The general gist is
  that if it tries to dial a node in the SAME datacenter (deduced by looking
  at the suffix of the node name) there is no change. If dialing a DIFFERENT
  datacenter it is wrapped up in a TLS+ALPN blob and sent through some mesh
  gateways to eventually end up in a server's :8300 port.

* a new flag when launching a mesh gateway via `consul connect envoy` to
  indicate that the servers are to be exposed. This sets a special service
  meta when registering the gateway into the catalog.

* `proxycfg/xds` notice this metadata blob to activate additional watches for
  the FederationState objects as well as the location of all of the consul
  servers in that datacenter.

* `xds:` if the extra metadata is in place additional clusters are defined in a
  DC to bulk sink all traffic to another DC's gateways. For the current
  datacenter we listen on a wildcard name (`server.<dc>.consul`) that load
  balances all servers as well as one mini-cluster per node
  (`<node>.server.<dc>.consul`)

* the `consul tls cert create` command got a new flag (`-node`) to help create
  an additional SAN in certs that can be used with this flavor of federation.

5 years ago

1 Commits (add-docs-for-anno)