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|This page contains historical information. It is probably no longer true.|
This device has been decommissioned.
|Icinga?:||host status services status|
|CPU:||2 x AMD Opteron(tm) Processor 248|
OBSOLETE: this server is no longer in service. (Oct 29 2010)
Ariel is the master DB server. Suda, the former master database server.
Note: As of 23 July 2005, samuel is the new master, and ariel is down.
Motherboard: AccelerTech HDAMA AT02161 - http://www.accelertech.com/products/motherboard/ATO2161.php
Yes, it has BIOS console redirection.
Some problems with kernel 2.6.7-rc3 on ariel. Some allocation_memory problems appear when stressing the machine. No more problems by disabling the swap.
Starting and stopping MySQL
- to start: sudo /usr/local/mysql/bin/mysqld_safe & (while logged in as a member of group wikidev). Normal response is Starting mysqld daemon with databases from /usr/local/mysql/var
- to stop: mysqladmin shutdown (use mysqladmin -uroot -p and supply the mysql root password if you don't have it in your my.cnf)
Process to switch to ariel
- In CommonSettings.php, set $wgReadOnlyFile
- Put read-only mysql on ariel
- in mysql shell:
mysql: set global read_only = on
- Switch user and server to ariel in CommonSettings.php
- $wgDBserver -> ariel (server)
- same user as Suda
- Disable linkscc, cause linkscc try to write. $wgEnablePersistentLC = false;
- Test wiki
- On suda, create an account for replicating the data.
mysql> GRANT REPLICATION SLAVE ON *.* -> TO 'repl'@'ariel-eth1' IDENTIFIED BY 'slavepass' ;
- To record the current log file name and offset, you should issue the following statements before you shutting down suda:
mysql> FLUSH TABLES WITH READ LOCK; mysql> SHOW MASTER STATUS;
- shut down suda without unlocking the tables to make sure that the server goes down with the snapshot corresponding to the current log file and offset:
shell> mysqladmin -u root shutdown
- Copy the db to ariel
- rsync -av /mnt/newdrive/newdata ariel:/usr/local/mysql/ --rsh=ssh --progress as root
- Alternative: Use netcat (nc) instead. Unencrypted and therefor faster. 10 MByte/s have been observed between ariel and zwinger.
- Stop mysql on Ariel
- remove symlink /usr/local/mysql/data
- mv /usr/local/mysql/newdata to /usr/local/mysql/data
- restart mysql on ariel
- Test wiki
- Set the master/slave: On Suda, do:
mysql> CHANGE MASTER TO -> MASTER_HOST='ariel-eth1', -> MASTER_USER='repl', -> MASTER_PASSWORD=' replication_password ', -> MASTER_LOG_FILE=' recorded_log_file_name ', -> MASTER_LOG_POS=recorded_log_position;
- Start the slave threads:
mysql> START SLAVE;