Fix low disk space maintenance

The setting didn't work because the code updated a status flag which
would be overwritten before being read. Also, promotion code now checks
that the server is not in maintenance.
This commit is contained in:
Esa Korhonen
2018-10-12 15:50:23 +03:00
parent 0c203fa02d
commit 2d61b78439
4 changed files with 28 additions and 24 deletions

View File

@ -875,3 +875,18 @@ void MariaDBMonitor::update_topology()
}
}
}
void MariaDBMonitor::set_low_disk_slaves_maintenance()
{
// Only set pure slave and standalone servers to maintenance.
for (MariaDBServer* server : m_servers)
{
if (server->is_low_on_disk_space() && server->is_usable()
&& !server->is_master() && !server->is_relay_master())
{
// TODO: Handle relays somehow, e.g. switch with a slave
MXS_WARNING("Setting %s to maintenance because it is low on disk space.", server->name());
server->set_status(SERVER_MAINT);
}
}
}

View File

@ -1676,20 +1676,6 @@ void MariaDBMonitor::enforce_read_only_on_slaves()
}
}
void MariaDBMonitor::set_low_disk_slaves_maintenance()
{
// Only set pure slave and standalone servers to maintenance.
for (MariaDBServer* server : m_servers)
{
if (server->has_status(SERVER_DISK_SPACE_EXHAUSTED) && server->is_usable()
&& !server->is_master() && !server->is_relay_master())
{
server->set_status(SERVER_MAINT);
m_cluster_modified = true;
}
}
}
void MariaDBMonitor::handle_low_disk_space_master()
{
if (m_master && m_master->is_master() && m_master->is_low_on_disk_space())

View File

@ -460,6 +460,13 @@ void MariaDBMonitor::tick()
update_external_master();
}
/* Set low disk space slaves to maintenance. This needs to happen after roles have been assigned.
* Is not a real cluster operation, since nothing on the actual backends is changed. */
if (m_maintenance_on_low_disk_space)
{
set_low_disk_slaves_maintenance();
}
// Sanity check. Master may not be both slave and master.
mxb_assert(m_master == NULL || !m_master->has_status(SERVER_SLAVE | SERVER_MASTER));
@ -532,13 +539,6 @@ void MariaDBMonitor::process_state_changes()
enforce_read_only_on_slaves();
}
/* Set low disk space slaves to maintenance.
*/
if (m_maintenance_on_low_disk_space && !m_cluster_modified)
{
set_low_disk_slaves_maintenance();
}
/* Check if the master server is on low disk space and act on it. */
if (m_switchover_on_low_disk_space && !m_cluster_modified)
{

View File

@ -1121,9 +1121,8 @@ bool MariaDBServer::can_be_demoted_failover(string* reason_out)
return demotable;
}
bool MariaDBServer::can_be_promoted(OperationType op,
const MariaDBServer* demotion_target,
std::string* reason_out)
bool MariaDBServer::can_be_promoted(OperationType op, const MariaDBServer* demotion_target,
string* reason_out)
{
bool promotable = false;
string reason;
@ -1134,6 +1133,10 @@ bool MariaDBServer::can_be_promoted(OperationType op,
{
reason = "it is already the master.";
}
else if (!is_usable())
{
reason = "it is down or in maintenance.";
}
else if (sstatus == NULL)
{
reason = string_printf("it is not replicating from '%s'.", demotion_target->name());