SQL Server 2019資料庫設定TDE加密後，導致備份檔bak過大

如果不想額外特別加MAXTRANSFERSIZE 參數
必須安裝SQL Server 2019 CU(Cumulative Update) 5 以上
因為微軟官網已經不提供CU5下載
可以安裝最新版的CU8 (KB4577194)

Cumulative Update 8 for SQL Server 2019
https://support.microsoft.com/en-us/help/4577194/cumulative-update-8-for-sql-server-2019

下載Cumulative Update Package 8 for SQL Server 2019 - KB4577194
https://www.microsoft.com/en-us/download/details.aspx?id=100809

SELECT @@VERSION結果
<安裝CU8之前>
Microsoft SQL Server 2019 (RTM-GDR) (KB4517790) - 15.0.2070.41 (X64)   Oct 28 2019 19:56:59   Copyright (C) 2019 Microsoft Corporation  Developer Edition (64-bit) on Windows Server 2019 Standard 10.0 <X64> (Build 17763: ) (Hypervisor)

<安裝CU8之後>
Microsoft SQL Server 2019 (RTM-CU8) (KB4577194) - 15.0.4073.23 (X64)   Sep 23 2020 16:03:08   Copyright (C) 2019 Microsoft Corporation  Developer Edition (64-bit) on Windows Server 2019 Standard 10.0 <X64> (Build 17763: ) (Hypervisor)


https://support.microsoft.com/en-us/help/4552255/kb4552255-cumulative-update-5-for-sql-server-2019
Bug Reference:13495908
KB article number:4561915
Improvement: MAXTRANSFERSIZE no longer required to enable backup compression on TDE encrypted databases

ref:
https://www.sqlshack.com/backup-compression-in-tde-enabled-databases-in-sql-server-always-on-availability-groups/

https://www.mssqltips.com/sqlservertip/4522/backup-compression-performance-enhancements-for-sql-server-2016-tde-enabled-databases/

台廠通過FIDO U2F & FIDO2認證的硬體：GoTrust Idem Key 動信安全金鑰

https://24h.pchome.com.tw/prod/DGAG76-A900ASZE9

一個820元
試過gmail和github都可以使用
網拍賣的其他FIDO水貨硬體比較貴

還可以跟手機配對用來登入Windows
https://www.youtube.com/watch?v=i8Z3-FKHTHc&t=81s

ref:
多奇技術分享會：漫談雙因子驗證與多階段驗證
https://www.facebook.com/watch/live/?v=241187464032358

免費安裝註冊RHEL(Red Hat Enterprise Linux)

因為CentOS 8之後政策修改，只好研究官方的RHEL如何安裝註冊
免費的Red Hat Developer Subscription授權僅限用於開發用途(development environment)

註冊Red Hat網站帳號
https://www.redhat.com

下載最新版ISO檔安裝
https://developers.redhat.com/products/rhel/download

下載舊版ISO檔、Supplementary、virt-p2v、KVM Guest Image、原始碼等(以RHEL 7.5為例)
https://access.redhat.com/downloads/content/69/ver=/rhel---7/7.5/x86_64/product-software

參考文件
https://developers.redhat.com/products/rhel/hello-world

查看已註冊的產品
https://access.redhat.com/management/subscriptions/

2021/02/01更新
小型企業可以免費使用16套授權
https://www.redhat.com/en/blog/new-year-new-red-hat-enterprise-linux-programs-easier-ways-access-rhel

• No-cost RHEL for small production workloads

• No-cost RHEL for customer development teams

紅帽推出免費與低成本RHEL計畫
https://www.ithome.com.tw/news/142391

FAQ: Changes to the Red Hat Developer program’s no-cost subscriptions
https://developers.redhat.com/articles/faq-changes-red-hat-developer-programs-no-cost-subscriptions
新政策只能安裝16個VM中
Under the new no-cost Red Hat Developer Subscription available from March 2018 onward, the maximum number of VMs supported by RHEL is now 16.
舊的
Program members who have activated the legacy Red Hat Enterprise Linux Developer Subscription may continue run up to 99 VMs inside their activated copy of Red Hat Enterprise Linux (RHEL.) 

透過指令註冊：
subscription-manager register
https://access.redhat.com/solutions/253273

透過介面註冊：

輸入subscription.rhn.redhat.com

MQ connection is terminating with error code 2009

某次系統升級IBM MQ Server從7升到9
新的Channel採用加密連線，一連線就出2009的錯誤
如果採不加密連線可以正常
後來發現是AP Client端的MQ Driver的jar檔沒有換成新版的
都不是以下六種原因@@

https://www.ibm.com/support/pages/mq-connection-terminating-error-code-2009

Problem

MQ connection is terminating with error code 2009.

Cause

The connection may be broken for a number of different reasons. The 2009 return code indicates that something prevented a successful connection to the Queue Manager. The most common causes for this are the following are:

1. A firewall that is terminating the connection
2. An IOException that causes the socket to be closed
3. An explicit action to cause the socket to be closed by one end
4. The queue manager is offline
5. The maximum number of channels allowed by the queue manager are open
6. A configuration problem in the Queue Connection Factory (QCF)

華碩ASUS ROG Zenith Extreme主機板8 DIMM記憶體插槽可以支援256GB記憶體

 https://news.xfastest.com/amd/58097/intel-128gb-amd-tr4-256gb/

華碩已經在ASUS ROG Zenith Extreme上實現了單條32GB non-ECC記憶體支援，這麼一來8 DIMM記憶體插槽就可以支援256GB記憶體

整批檔案轉編碼工具:UTFCast

 https://www.rotatingscrew.com/downloads.aspx

 

UTFCast 批次轉換文件為 UTF8 編碼
https://briian.com/7120/

 

純文字檔案的編碼與內文批次轉換：Big5轉UTF-8
http://blog.pulipuli.info/2018/08/big5utf-8-batch-convert-plain-text.html#postcatabig5utf-8-batch-convert-plain-text.html0_anchor2

SQL SERVER針對熱資料表(讀寫比率很高)停用鎖定擴大

alter table 資料表名稱 set (LOCK_ESCALATION=disable)
停用會增加記憶體使用量，前提是伺服器記憶體充足

 https://dotblogs.com.tw/ricochen/2015/10/24/153680

https://dotblogs.com.tw/ricochen/2012/02/17/69565

https://medium.com/codxfrankenstein/sql-server-%E9%8E%96%E5%AE%9A%E6%93%B4%E5%A4%A7-af9a425e4e3b