Drop Down MenusCSS Drop Down MenuPure CSS Dropdown Menu

How to run a script at background and How to monitor and how to shedule a job using crontab easily ?

-

 By giving" &" at end of script called running background

                            (OR)

Set in task scheduler or crontjob.

Using at command you can schedule a job to run at a particular date and time. For example, to execute the backup script at 5 a.m tomorrow, do the following.

$ at -f backup.sh 5 am tomorrow

you can run the shell script Following methods at backgroundly:

. script.sh &
./script.sh &
sh script.sh &
       (OR)
nohub sh script.sh &
nohub ./script.sh &
nohub .script.sh &

Note: hup is a hangup signal... nohup - no hangup... so if we give  nohup script.sh & ... it starts progressing script.sh in back ground... that the subsequent logout or session disconnection does not stop..

Note: & Stands for running background

After running this give  "ctrl+z" in background one id will be displayed as running that is called  process_ID using that PID we can adjust priority for that particular jobs.

jobs -l (will display that process id which is running )

Note: jobs will be displayed only the running and stopped jobs for only that session

top -c is also one of option -c means which display the commands. But This will be displayed whole server jobs and services not for session only


if you want commands

screen Sh script.sh

Here are the steps you can follow to run a process in screen, detach from the terminal, and then reattach.

From the command prompt, just run screen. This will give you a new subshell.

Run your desired program

Detatch from the screen session using the key sequence Ctrl-a Ctrl-d (note that all screen key bindings start with Ctrl-a). This will drop you back to your original shell and display a message "[detached]", indicating that the screen session is still running.

You can then list the available screen sessions by running "screen -list"

You can reattach to this screen session by running "screen -r". Once reattached, you will be able to take off where you left off and see any output that was printed to the screen during the time that you were detached. If you have multiple screen sessions, then you can specify the tty name (as displayed by screen -list) as an argument to screen -r to attach to a particular session.

Comments

Post a Comment

Popular posts from this blog

How to find the server is whether standby (slave) or primary(master) in Postgresql replication ?

-
Method 1 You can check the mode of the server using "pg_controldata". [pgsql@test~]$ pg_controldata /usr/local/pgsql/data84/ Database cluster state: in archive recovery --> This is Standby Database Database cluster state: in production --> This is Production Database [Master] Method 2 You can use pg_is_in_recovery() which returns True if recovery is still in progress(so the server is running in standby mode or slave) postgres=# select pg_is_in_recovery(); pg_is_in_recovery ------------------- t (1 row) If Return    false   so the server is running in primary mode or master postgres=# select pg_is_in_recovery(); pg_is_in_recovery ------------------- f (1 row)
Read more

How to Get Table Size, Database Size, Indexes Size, schema Size, Tablespace Size, column Size in PostgreSQL Database

-
In this post, I am sharing few important function for finding the size of database, table and index in PostgreSQL. Finding object size in postgresql database is very important and common. Is it very useful to know the exact size occupied by the object at the tablespace. The object size in the following scripts is in GB. The scripts have been formatted to work very easily with PUTTY SQL Editor. 1. Checking table size excluding table dependency: SELECT pg_size_pretty(pg_relation_size('mhrordhu_shk.mut_kharedi_audit')); pg_size_pretty ---------------- 238 MB (1 row) 2. Checking table size including table dependency: SELECT pg_size_pretty(pg_total_relation_size('mhrordhu_shk.mut_kharedi_audit')); pg_size_pretty ---------------- 268 MB (1 row) 3. Finding individual postgresql database size SELECT pg_size_pretty(pg_database_size('db_name')); 4. Finding individual table size for postgresql database -including dependency index: SELECT pg_size_pretty(pg_total_rel
Read more

7 Steps to configure BDR replication in postgresql

-
Image
 The  BDR  (Bi-Directional Replication) project adds multi-master replication to PostgreSQL 9.4.  Postgres-BDR has a lower impact on the masters(s) than trigger-based replication solutions. There is no write-amplification, as it does not require triggers to write to queue tables in order to replicate writes.   Here We are using  postgres version 9.4.12 and bdr version 1.0.2. for configuring  multi master replication . Simply Following 7 steps you can configure the multi master replication in postgresql. To download the bdr in below link. .   https://github.com/2ndQuadrant/bdr/archive/bdr-pg/REL9_4_12-1.tar.gz $ tar -xzvf REL9_4_12-1.tar.gz $ wget https://github.com/2ndQuadrant/bdr/archive/bdr-plugin/1.0.2.tar.gz $ tar -xzvf 1.0.2.tar.gz 1. To install BDR. $ cd ~/bdr-bdr-pg-REL9_4_12-1 $ ./configure --prefix=/usr/lib/postgresql/9.4 --enable-debug --with-openssl $ make -j4 -s install-world $ cd ~/bdr-bdr-plugin-1.0.2 $ PATH=/usr/lib/postgresql/9.4/bin:"$PATH" ./c
Read more

Postgres Streaming Replication Configuration

-
Primary - Existing Test Server: ======= Hostname: nijam-1 IP Address: 53.99.198.11 Secodary - New Test Server ======== Hostname: nijam-2 IP Address: 53.99.198.12 ===================================================== Step 1. stop the slave server /optt/10.5/bin/pg_ctl -D /DATA stop Step 2. move the slave data directory to backup location: mv /DATA/* /tmp/backup Step 3. change below parameter on master postgresql.conf & pg_hba.conf files . listen_addresses = 'localhost,53.99.198.11' wal_level = replica # minimal, replica, or logical archive_mode = on archive_command = 'cp %p /ARCHIVES/%f' max_wal_senders = 10 wal_keep_segments = 25 On pg_hba.conf: host replication postgres 53.99.198.12/24 trust host replication postgres 53.99.198.11/24 trust Step 4. Restart the master server: /optt/10.5/bin/pg_ctl -D /DATA restart Step 5. taking consistancy backup: psql -c "sele
Read more

vacuumlo - removing large objects orphans from a database PostgreSQL

-
vacuumlo   is a simple utility program that will remove any   “ orphaned ”   large objects from a   PostgreSQL   database. An orphaned large object (LO) is considered to be any LO whose OID does not appear in any   oid   or   lo   data column of the database. OIDs basically give you a built-in, globally unique id for every row,default is on( default_with_oids ( boolean )). If you use this, you may also be interested in the   lo_manage   trigger in the   lo   module.   lo_manage   is useful to try to avoid creating orphaned LOs in the first place. More about lo module  there are two ways to store large objects in the PostgreSQL:   bytea oid and lo  Working process of vacuumlo: First, vacuumlo builds a temporary table which contains all of the OIDs of the large objects in the selected database. It then scans through all columns in the database that are of type oid or lo, and removes matching entries from the temporary table. (Note: only types with these names are con
Read more