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<<Back to Exadata Main Page What is IPMI tool ipmitool - utility for controlling IPMI-enabled devices. Its a technology that gives administrators almost total control over remotely deployed servers. IPMI let remote administrators monitor the health of servers, deploy (or remove) software, manage hardware peripherals like the keyboard and mouse, reboot the system and update software on it, independent of the operating system. You can use this utility to perform IPMI functions with a kernel device driver or over a LAN interface. It's a powerful protocol that is supported by many late model server hardware from major manufacturers like Dell, HP, Oracle and Lenovo. Note - Your server includes a number of IPMI-compliant sensors that measure things such as voltages, temperature ranges, and security latches that detect when the enclosure is opened. For a complete list of sensors, see your platform specific guide. How to check if a device is IPMI-enabled you can use dmideco...

<<Back to MySQL & MariaDB How To Page How to rename an user in Mysql or MariaDB. There are many possible ways to rename an user in maria DB but in this post I will introduce you with rename command Syntax : RENAME USER 'username'@'host' TO 'new_username'@'host'; MariaDB [(none)]> select user,host from mysql.user where user like '%anand%'; +--------------+---------------------------+ | user         | host                      | +--------------+---------------------------+ | anand_tiwari | d-test-pyx%.test.com | | anand_tiwari | localhost                 | +--------------+---------------------------+ 2 rows in set (0.00 sec) I want to rename my account anand_tiwari@d-test-pyx%.test.com to anand_tiwari@d-test-pyx01.test.com MariaDB ...

<<Back to MySQL & MariaDB Main Page I am struggling with maxscale basic authentication and wanted to find out some workaround. There are several limitation while using maxscale (eg. MaxScale can not manage authentication that uses wildcard matching in hostnames in the mysql.user table of the backend database. The only wildcards that can be used are in IP address entries.) mariadb-maxscale-limitations-and-known-issues So I was trying to find out all the user@host combination having % (wildcard) in its hostname. This took me a while, to find a way to negate the effect of an special character in MySQL and MariaDB and this motivated me to write this blog today. What is wildcard filtering? Wildcard filtering is a mechanism for comparing text in a column against a search pattern. eg. Example 1 SELECT user, host FROM mysql.user WHERE user LIKE '%tiwari_anand%'; This query will retrieve all users and its hostname from mysql.user table if the user contains the strin...

<<Back to MySQL & MariaDB How To Page MySQL & MariaDB- The Power of Show Command show command in MySQL or MariaDB is really very useful and  being a DBA we need to use it very often to perform the daily tasks. Let us have a look hat we can do with this show command MariaDB [(none)]> help show; Name: 'SHOW' Description: SHOW has many forms that provide information about databases, tables, columns, or status information about the server. This section describes those following: SHOW AUTHORS SHOW {BINARY | MASTER} LOGS SHOW BINLOG EVENTS [IN 'log_name'] [FROM pos] [LIMIT [offset,] row_count] SHOW CHARACTER SET [like_or_where] SHOW COLLATION [like_or_where] SHOW [FULL] COLUMNS FROM tbl_name [FROM db_name] [like_or_where] SHOW CONTRIBUTORS SHOW CREATE DATABASE db_name SHOW CREATE EVENT event_name SHOW CREATE FUNCTION func_name SHOW CREATE PROCEDURE proc_name SHOW CREATE TABLE tbl_name SHOW CREATE TRIGGER trigger_name SHOW CR...

<<Back to Exadata Main Page We got email alert from one dom0 machine in X5-2 Eighth Rack HC 8 TB: DiskControllerFirmwareRevision Unknown. Looks like LSI MegaRAID controler info cannot be fetched.  domU machines running under this dom0 are still working properly. # dbmcli -e list physicaldisk 252:0 B7G5GA normal 252:1 B7HPXA failed 252:2 B7J55A failed 252:3 B6RT7A failed # /opt/MegaRAID/MegaCli/MegaCli64 -adpallinfo -a0 | grep -i package   ]# <<<<<<------- BLANK ]# /opt/MegaRAID/MegaCli/MegaCli64 /c0 show termlog  Controller = 0 Status = Failure Description = Controller 0 not found Solution :Oracle engineer replaced this "suspected" RAID controller Further Issue: Even after replacing the RAID controller the Amber LED in the ILOM of on Exadata Compute nodes was not cleared. The solution is documented in  Doc ID 2111921.1 How to clear AMBER LED on Exadata Compute nodes when Compute Node disks report offline but no fault detected by R...

<<Back to Exadata Main Page If you are receiving notification like this, it means there is something wrong and you must take prompt action. Attribute Name DiskControllerModel Required LSI MegaRAID 9361-8i Found Unknown Attribute Name DiskControllerFirmwareRevision Required 24.3.0-0084 Found Unknown Quick Verification # dbmcli -e list physicaldisk 252:0 B7G5GA normal 252:1 B7HPXA failed 252:2 B7J55A failed 252:3 B6RT7A failed # /opt/MegaRAID/MegaCli/MegaCli64 -adpallinfo -a0 | grep -i package  # <<<<<<------- BLANK # /opt/MegaRAID/MegaCli/MegaCli64 /c0 show termlog  Controller = 0 Status = Failure Description = Controller 0 not found. IF ASR is in place manually open service request for oracle to investigate and fix the issue Solution in my case Oracle engineer replaced this "suspected" RAID controller. # dbmcli -e list physicaldisk ...

<<Back to Exadata Main Page What is Oracle Exadata The Oracle Exadata Database Machine is a combined compute and storage system marketed for running Oracle Database software. It primarily consists Storage Grid (Storage Machines) Compute Grid (Database Machines) Network Grid (Network Components) An oracle Exadata machine comes as Full Rack, Half Rack, Quarter Rack and Eighth Rack. An overview of hardware configuration and differences among them are presented in the below table Hardware Components of Oracle Exadata Database Machine Edition Oracle Exadata Database Machine Full Rack Oracle Exadata Database Machine Half Rack Oracle Exadata Database Machine Quarter Rack Oracle Exadata Database Machine Eighth Rack Oracle Exadata Database Machine X7-2 8 database servers 4 database servers 2 database servers 2 database servers. Each server has 1x 24-core processor with all 24-cores enabled 14 Exadata Storage Ser...