ssh_exchange_identification: Connection closed by remote host
重启SSH Server (OpenSSH)即可解决，但是你都登不上去，怎么重启呢。
如果你装了CPANEL，可以登录进WHM重启。
如果你的主板支持Remote Console Redirect，可以直接连进去重启。
最后一个办法，要求机房重新启动服务器。
这个问题没有什么特别的根源，就是SSH SERVER本身运行过久不稳定了。
服务器Non Payment费
3月份在MidPhase月付租了两个服务器跑XRUMER，后来决定不用，就放在那里等他自己Terminate。前两天有需求要再租用一台，结果去的时候，人家要求结清之前的Non Payment费用。仔细看了TOS，还真的有这一说，如果不用的话要提前7天告知。
以后用这种周期性付钱的东西还是要注意点结算时间，免得再次造成困扰。
Magento无法更新索引故障
更新索引报错：There was a problem with reindexing process.
后台开启LOG，重现故障。
检查var/log/exception.log
发现如下错误：
2011-09-02T01:34:53+00:00 DEBUG (7): Exception message: SQLSTATE[HY000]: General error: 1005 Can't create table 'goodsite_default.catalog_category_flat_store_11' (errno: 150)
Trace: #0 /home/goodsite/public_html/lib/Zend/Db/Statement.php(300): Zend_Db_Statement_Pdo->_execute(Array)
#1 /home/goodsite/public_html/lib/Zend/Db/Adapter/Abstract.php(468): Zend_Db_Statement->execute(Array)
#2 /home/goodsite/public_html/lib/Zend/Db/Adapter/Pdo/Abstract.php(238): Zend_Db_Adapter_Abstract->query('CREATE TABLE `c...', Array)
#3 /home/goodsite/public_html/lib/Varien/Db/Adapter/Pdo/Mysql.php(333): Zend_Db_Adapter_Pdo_Abstract->query('CREATE TABLE `c...', Array)
#4 /home/goodsite/public_html/app/code/core/Mage/Catalog/Model/Resource/Eav/Mysql4/Category/Flat.php(523): Varien_Db_Adapter_Pdo_Mysql->query('CREATE TABLE `c...')
#5 /home/goodsite/public_html/app/code/core/Mage/Catalog/Model/Resource/Eav/Mysql4/Category/Flat.php(430): Mage_Catalog_Model_Resource_Eav_Mysql4_Category_Flat->_createTable('11')
#6 /home/goodsite/public_html/app/code/core/Mage/Catalog/Model/Category/Indexer/Flat.php(237): Mage_Catalog_Model_Resource_Eav_Mysql4_Category_Flat->rebuild()
#7 /home/goodsite/public_html/app/code/core/Mage/Index/Model/Process.php(139): Mage_Catalog_Model_Category_Indexer_Flat->reindexAll()
#8 /home/goodsite/public_html/app/code/core/Mage/Index/Model/Process.php(167): Mage_Index_Model_Process->reindexAll()
#9 /home/goodsite/public_html/app/code/core/Mage/Index/controllers/Adminhtml/ProcessController.php(124): Mage_Index_Model_Process->reindexEverything()
#10 /home/goodsite/public_html/app/code/core/Mage/Core/Controller/Varien/Action.php(418): Mage_Index_Adminhtml_ProcessController->reindexProcessAction()
#11 /home/goodsite/public_html/app/code/core/Mage/Core/Controller/Varien/Router/Standard.php(254): Mage_Core_Controller_Varien_Action->dispatch('reindexProcess')
#12 /home/goodsite/public_html/app/code/core/Mage/Core/Controller/Varien/Front.php(177): Mage_Core_Controller_Varien_Router_Standard->match(Object(Mage_Core_Controller_Request_Http))
#13 /home/goodsite/public_html/app/code/core/Mage/Core/Model/App.php(304): Mage_Core_Controller_Varien_Front->dispatch()
#14 /home/goodsite/public_html/app/Mage.php(596): Mage_Core_Model_App->run(Array)
#15 /home/goodsite/public_html/index.php(390): Mage::run('', 'store')
#16 {main}
检查/home/goodsite/public_html/app/code/core/Mage/Catalog/Model/Resource/Eav/Mysql4/Category/Flat.php文件第 523 行附近
$_tableSql .= "PRIMARY KEY (`entity_id`),
KEY `IDX_STORE` (`store_id`),
KEY `IDX_PATH` (`path`),
KEY `IDX_LEVEL` (`level`),
CONSTRAINT `FK_CATEGORY_FLAT_CATEGORY_ID_STORE_{$store}` FOREIGN KEY (`entity_id`)
REFERENCES `{$this->getTable('catalog/category')}` (`entity_id`) ON DELETE CASCADE ON UPDATE CASCADE,
CONSTRAINT `FK_CATEGORY_FLAT_STORE_ID_STORE_{$store}` FOREIGN KEY (`store_id`)
REFERENCES `{$this->getTable('core/store')}` (`store_id`) ON DELETE CASCADE ON UPDATE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=utf8";
$this->_getWriteAdapter()->query($_tableSql);
删除掉ENGINE=InnoDB，改用MyISAM表，成功。
至于为什么用InnoDB不行，我也不知道，这个案例里已存在的所有的表都是MyISAM的。可能在一开始就是个错误，而至少现在一切工作正常了。