MySQLAuth requires the SHOW DATABASES privilege to see all the databases
so it should be checked that the current user has the permission. A
missing permission will cause errors that are hard to resolve.
When the IO thread of a relay master is stopped, the knowledge that it is
not a real master but a relay master is lost. To prevent this loss of
information, the master server's server_id value should always be stored
if it is available.
If a server is removed from a service, readconnroute will not verify that
the server it is connected to is still the same root master. This fixes
the regression of MXS-1418.
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.
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.
Removed false error message about failed session commands. An error in
response to a session command is a perfectly valid result.
Also added the explicit commands that the master and slave return to the
warning that is logged when the results differ.
The debug assertion wasn't well placed as it is perfectly possible that a
master connnection exists but it is not in use. This can be further
checked by asserting that the master is indeed closed and not in use.
Moved the original debug assertion into a separate branch that should
catch any errors in the routing logic.
When detect_standalone_master is enabled, the root_master variable was not
updated after the master was changed by the standalone server detection
mechanism. This caused debug assertions to fire in addition to possibly
causing some of the ignore_external_masters logic to break.
"servers_no_promotion" is a comma-separated list of servers
which cannot be chosen when selecting a new master during failover
(auto or manual), or when automatically selecting a new master
for switchover (currently disabled).
The servers in the list are redirected normally and can be promoted
by switchover when manually selecting a new master.
The Master status now prevents Slave status from being assigned to a
server. In practice this simply means that the master will not have both
the Master and Slave status bits.
By always starting the session shutdown process by stopping the client
DCB, the manipulation of the session state can be removed from the backend
protocol modules and replaced with a fake hangup event.
Delivering this event via the core allows the actual dcb_close call on the
client DCB to be done only when the client DCB is being handled by a
worker.
Directly closing the client DCB in the backend protocol modules is not
correct anymore as the state of the session doesn't change when the client
DCB is closed. By propagating the shutdown of the session with a fake
hangup to the client DCB, the closing of the DCB is done only once.
Added debug assertions that make sure all DCBs are closed only
once. Removed redundant code in the backend protocol error handling code.
The token skipping function did not check for a period or an opening
parenthesis when parsing the test. Also fixed a debug assertion when only
NULL values were inserted.
In debug mode, when scanning the server id from a string, check that resulting
number is 32bit. Also, when querying the server id, query the global version.
Now, if a super user modifies the server id the monitor will notice it.
Server id:s in gtid:s are handled similarly.
As chages to the transaction state are detected by the protocol level
mini-parser, there's no need to fully classify queries inside read-only
transactions. This should be a good performance boost for loads that
heavily use read-only transactions.
If a DCB is closed before a response to the handshake packet is received,
the DCB's session will point to the dummy session. In this case no error
should be written to the DCB.
Now detects some erroneous situations before starting switchover.
Switchover can be activated without specifying current master.
In this case, the cluster master server is selected.
Used the correct value in table_create_alloc and remove unused
parameter. Use the pre-calculated end pointer when looking for events.
Always use the column count of the TABLE_MAP event as all mismatches are
detected earlier.
