The package descriptions, summaries and licenses now use a generic
mechanism. This makes it easier to add new components that only include
small parts or use a different license.
Also updated the descriptions, the license versions and package summaries
for the main packages.
Previously, if the list contained servers that were not monitored by
the monitor yet were valid servers, an error value would be returned
and the monitor failed to start.
With this update, the non-monitored servers are simply ignored when
forming the final list.
Also, added printing of the list to diagnostics.
Now the users will be reloaded at most once during each
USERS_REFRESH_TIME period. Earlier they could be reloaded at
at most USERS_REFRESH_MAX_PER_TIME times, which in practice meant
that with repeated unauthorized login attempts they were reloaded
N times in rapid succession, without the situation being likely to
change in between.
The error regarding the refresh rate having been exceeded
error: [RWSplit] Refresh rate limit exceeded ...
has been turned into a warning. Further, the warning will be
logged at most once per refresh period that currently is 30s.
This is used only in case of everything else fails and this lookup
is not unlikely to fail if the client comes from some machine on
an internal network.
If the master is replicating from an external master, the monitor will save the
host:port of the external server. During demotion, the old master stops the external
replication while the new master begins it. Also, any commands that would add
to gtid have to be omitted when an external master is in play.
When a BEGIN statement is prepared using the binary protocol, it returns a
single OK packet. Due to a bug in the code that deals with multi-statement
results and EOF packets, the response was never sent to the client.
Also added back the error messages of failed session commands to the INFO
level. This way it's still possible to see why a session command fails but
the log isn't flooded by them in normal usage.
The tests are now built by default. This should make it easier for users
to verify that they have a working MaxScale.
Also made the building of test_parse_kill conditional like the rest of the
tests.
When four servers (A, B, C and E where E and A replicate from each other
and A is the master for B and C) form a cluster and only three of them (A,
B and C) are configured into MaxScale, a failover operation from A to B
(making B the current master) and a restart of A causes B to lose its
master status.
The following diagram illustrates the state of the cluster at the end of
the process described above.
+----------------------+
| +---+ |
+------------+ B <-+ |
+-v-+ | +---+ | |
| E | | | |
+-^-+ | +---+ +-+-+ |
+------+ A | | C | |
| +---+ +---+ |
| |
+----------------------+
The external server E was not correctly ignored in the replication
topology generation causing both A and B to be seen as the lowest slave
nodes in the tree. From a theoretical point of view this is the correct
interpretation as there are two distinct trees and neither of them
contains any true masters.
In practice, MaxScale should treat any servers that replicate from an
external master as root level master nodes. Doing this guarantees that they
are labeled as masters if they have slaves replicating from them.
The responses of slaves that arrived before the master were always
compared to the empty value of 0x00. If the slave connection replied after
the master, the comparison was correct.
This commit introduces a map of slaves and their responses that
are handled once the master's response arrives.
