The new field `compression` in the `cluster{}` block allows to
specify which compression mode to use between servers.
It can be simply specified as a boolean or a string for the
simple modes, or as an object for the "s2_auto" mode where
a list of RTT thresholds can be specified.
By default, if no compression field is specified, the server
will use the s2_auto mode with default RTT thresholds of
10ms, 50ms and 100ms for the "uncompressed", "fast", "better"
and "best" modes.
```
cluster {
..
# Possible values are "disabled", "off", "enabled", "on",
# "accept", "s2_fast", "s2_better", "s2_best" or "s2_auto"
compression: s2_fast
}
```
To specify a different list of thresholds for the s2_auto,
here is how it would look like:
```
cluster {
..
compression: {
mode: s2_auto
# This means that for RTT up to 5ms (included), then
# the compression level will be "uncompressed", then
# from 5ms+ to 15ms, the mode will switch to "s2_fast",
# then from 15ms+ to 50ms, the level will switch to
# "s2_better", and anything above 50ms will result
# in the "s2_best" compression mode.
rtt_thresholds: [5ms, 15ms, 50ms]
}
}
```
Note that the "accept" mode means that a server will accept
compression from a remote and switch to that same compression
mode, but will otherwise not initiate compression. That is,
if 2 servers are configured with "accept", then compression
will actually be "off". If one of the server had say s2_fast
then they would both use this mode.
If a server has compression mode set (other than "off") but
connects to an older server, there will be no compression between
those 2 routes.
Signed-off-by: Ivan Kozlovic <ivan@synadia.com>
New configuration fields:
```
cluster {
...
pool_size: 5
accounts: ["A", "B"]
}
```
The configuration `pool_size` in the example above means that this
server will create 5 routes to a remote server, assuming that that
server has the same `pool_size` setting.
Accounts (which are not part of the `accounts[]` configuration)
are assigned a specific route in this pool, and this will be the
same route on all servers in the cluster.
Accounts that are defined in the `accounts` field will each have
a dedicated route connection. This will allow suppression of the
account name in some of the route protocols, reducing bytes transmitted
which may increase performance.
Signed-off-by: Ivan Kozlovic <ivan@synadia.com>
Added cluster names as required for prep work for clustered JetStream. System can dynamically pick a cluster name and settle on one even in large clusters.
Signed-off-by: Derek Collison <derek@nats.io>
This has an effect only on connections created by the server,
so routes and gateways (explicit and implicit).
Make sure that an explicit warning is printed if the insecure
property is set, but otherwise allow it.
Resolves#1062
Signed-off-by: Ivan Kozlovic <ivan@synadia.com>
For cluster, we allow to skip hostname verification from certificate.
We now print a warning when this option is enabled, both on startup
or if the property is enabled on config reload.
Signed-off-by: Ivan Kozlovic <ivan@synadia.com>
Based on @softkbot PR #913.
Removed the command line parameter, which then removes the need for Options.Cluster.TLSInsecure.
Added a test with config reload.
Signed-off-by: Ivan Kozlovic <ivan@synadia.com>
Refactor the way client is initialized. We need to ensure that
clients are not added to the clients map and readLoop started if
the server is in the process of being shutdown otherwise there
is a chance that the server already gathered the list of connections
to close and this one would not be included, leaving a readLoop
running.
Same occurs for routes, with the complexity that the readLoop is
started well before the route connection is added to the server
routes' list. We need a temporary map that contains those connections
to be able to close them on server Shutdown.
Fixed some flapping tests.
Both seed and chained cases are now handled properly when servers
connect quickly and concurrently to one another.
When accepting a route, the server will forward the new route INFO
protocol to its known routes. In turn those routes will connect
to the new server (if not already connected).
A retry for implicit route was introduced to mitigate the issue
with two servers connecting to each other and electing the opposite
connection as the winner, resulting in both connections being dropped.
The server with smaller ID will try once to reconnect.
Some tests were fixed to handle possible extra INFO protocol.
New tests added.
Fix issue: https://github.com/nats-io/gnatsd/issues/206
