sh -c 'echo "deb http://apt.postgresql.org/pub/repos/apt/ `lsb_release -cs`-pgdg main" >> /etc/apt/sources.list.d/pgdg.list'
wget -q https://www.postgresql.org/media/keys/ACCC4CF8.asc -O - | apt-key add -
apt update
apt install postgresql-9.4
script /dev/null
screen
postgresql check databases for errors
pg_dumpall -f /dev/null 2> /tmp/pg.err
mysqldump --single-transaction sourcedb | ssh remote_server_ip 'mysql destinationdb'
apt install hping3
hping3 -c 15000 -d 120 -S -w 64 -p 80 –flood –rand-source 192.168.1.100
systemctl stop mongod.service
apt update
apt install mongodb-org=3.6.8 mongodb-org-mongos=3.6.8 mongodb-org-server=3.6.8 mongodb-org-shell=3.6.8 mongodb-org-tools=3.6.8
systemctl start mongod.service
mongo
db.adminCommand( { setFeatureCompatibilityVersion: "3.6" } )
db.adminCommand( { getParameter: 1, featureCompatibilityVersion: 1 } )
vi /etc/apt/sources.list.d/mongodb-org-4.0.list
deb [arch=amd64] https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.0 multiverse
apt update mongodb*
apt upgrade
#include
#include
struct utmp foo;
main()
{
printf("%lu\n", sizeof foo);
return 0;
}
Perl:
$utmp_size = utmp_record_size_goes_here;
$wtmp_file = "wtmp filename goes here";
open WTMP, "+<", $wtmp_file or die "$wtmp_file: ", $!;
seek WTMP, -10 * $utmp_size, 2;
truncate WTMP, tell(WTMP);
close WTMP;
* * * * * /usr/bin/flock -w 0 /tmp/cron.lock /usr/bin/php7.4 /path/to/cron.php
vim /etc/php/7.4/cli/php.ini;
short_open_tag=On;
pt-online-schema-change alters a table’s structure without blocking reads or writes. Specify the database and table in the DSN. Do not use this tool before reading its documentation and checking your backups carefully.
parted -s -a optimal -- /dev/sdX mkpart primary 1MiB -2048s
show slave mysql
mysql> SELECT * FROM information_schema.PROCESSLIST AS p WHERE p.COMMAND = 'Binlog Dump';
+---------+------+-------------------------+------+-------------+---------+---------------------------------------------------------------+------+
| ID | USER | HOST | DB | COMMAND | TIME | STATE | INFO |
+---------+------+-------------------------+------+-------------+---------+---------------------------------------------------------------+------+
| 3973053 | user | srv-mysql-slave1:53014 | NULL | Binlog Dump | 3743978 | Master has sent all binlog to slave; waiting for more updates | NULL |
+---------+------+-------------------------+------+-------------+---------+---------------------------------------------------------------+------+
grow xfs:
xfs_growfs /dev/vg_test/lv_test
Command: MLSD
Error: The data connection could not be established: ECONNREFUSED - Connection refused by server
Error: Connection timed out after 60 seconds of inactivity
Error: Failed to retrieve directory listing
echo "40000 45000" > /etc/pure-ftpd/conf/PassivePortRange
echo "1.2.3.4" > /etc/pure-ftpd/conf/ForcePassiveIP
service pure-ftpd restart
UPDATE mysql.db SET Host='%' WHERE Host='localhost' AND User='username';
FLUSH PRIVILEGES;