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--- linux:scribble [2017/05/16 13:34] – add tricks for Jenkins stybla
+++ linux:scribble [2021/07/01 07:42] – add Move LVM on LUKS to new HDD stybla
@@ Line 110: / Line 110: @@
 data[1] = number >> 0;
 </code>
+===== Exercises ======
+[[https://www.codingunit.com/category/programming-algorithms|Programming algorithms at CodingUnit]].
@@ Line 269: / Line 273: @@
 multilibs from time to time), so that might be the issue behind error above. But libvirt
 is long gone, replaced and forgotten now.
+===== Move LVM on LUKS to new HDD =====
+Unfortunately, this is like two years later and all I have are two links - [[https://wiki.deimos.fr/images/f/f1/How_To_Migrate_to_a_full_encrypted_LVM_system.pdf|first]] and [[https://unix.stackexchange.com/questions/379357/best-way-to-move-lvm-on-luks-to-a-new-hdd|second]]. I believe the first one shows how to initialize LUKS at new HDD while the second explains how to move LVM. Shameless copy-paste from the second link. I'm NOT the author of the following:
+> Ideally, you initialize the new LUKS partition as a LVM PV, add it to your volume group with:
+<code>vgextend vg1 /path/to/new/LUKS/device</code>
+> Then use the LVM pvmove command to migrate your data to it like so:
+<code>pvmove /path/to/old/LUKS/device /path/to/new/LUKS/device</code>
+> When the data migration is done, be sure to remove the old LUKS partition from the volume group with:
+<code>vgreduce vg1 /path/to/old/LUKS/device</code>
+> This can all be done with the system online, although it is marginally safer and probably significantly faster to do it from a LiveCD like SystemRescueCD. Also, if you have a new enough version of LVM, you probably want to use the --atomic option for pvmove, that will ensure that you don't end up with some LV's on the new device and some on the old device if the pvmove command fails.
+I wish I've documented all the steps I took to move LUKS between HDDs since it might come handy. Also, it's not the first time I did that. Damn!
 ===== loop-AES =====
@@ Line 301: / Line 325: @@
 Funny thing is, it seems much harder to resize encrypted partition via cryptsetup/dm-crypt.
+===== MySQL =====
+==== Convert database to UTF-8 encoding ====
+Originally found at [[https://www.a2hosting.com/kb/developer-corner/mysql/convert-mysql-database-utf-8|a2hosting.com]]
+Run mysql and check the encoding:
+<code>
+SELECT default_character_set_name FROM information_schema.SCHEMATA S WHERE schema_name = "DBNAME";
+SELECT CCSA.character_set_name FROM information_schema.`TABLES` T,information_schema.`COLLATION_CHARACTER_SET_APPLICABILITY` CCSA WHERE CCSA.collation_name = T.table_collation AND T.table_schema = "DBNAME" AND T.table_name = "TABLENAME";
+</code>
+Change encoding of tables:
+<code>
+cat > ~/.my.cnf <<EOF
+[client]
+user=USER
+password=PASSWORD
+EOF
+mysql --database=DBNAME -B -N -e "SHOW TABLES" | awk '{print "SET foreign_key_checks = 0; ALTER TABLE", $1, "CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci; SET foreign_key_checks = 1; "}' | mysql --database=DBNAME
+</code>
+Change encoding of DB itself:
+<code>
+ALTER DATABASE DBNAME CHARACTER SET utf8 COLLATE utf8_general_ci;
+</code>
+Remove ''~/.my.cnf'' or edit out username and password.
 ===== OpenOffice/LibreOffice =====