vi

Cluster SSH tool Utility

Many times you come across scenario’s when you wish to open multiple ssh windows and execute same commands.e.g You wish to see alert log for multi-node RAC simultaneously or edit sysctl.conf files for multiple machines.

Cluster SSH utility helps solve this problem as it opens multiple SSH sessions and allows simultaneous control.

In case you are using MAC OS X, you can download from Google Code site . Utility is called csshX.

For Linux you can download from Sourceforge site and utility is called Cluster SSH.

I am using csshX to show demo. Suppose I have 3 hosts host1,host2,host3 I need to use following commands on terminal app

$csshX host1 host2 host3

or

$csshX host[1-3]

As you can see we can specify range using square brackets.  csshX will create an SSH session to each remote host in separate Terminal.app windows. A master window will also be created. All keyboard input in the master will be sent to all the slave windows. Below screenshot displays how windows will look like

I can enter commands in Master (Red Color) window and it will execute same commands in all 3 windows.If you want to execute commands in particular window then go directly  to that window.  In case we need to open 3 sessions for host1 then we execute

$csshx host1+3
26 January, 2012 by Unix 0

Use awk/sed in vi

Thought of sharing some useful info which can help you to do your work faster in vi.You can use awk/sed scripts in vi using following command in vi
:%!scriptname
Here the scriptname file should have execute privilges for user. I used this to create a useful script which I was doing by typing multiple substitution command in vi.
e.g Your file contains list of table
$cat t.lst
BANK005
BJSTM
BJS_ORG
CHAINED_ROWS
CORR_BAM
CORR_CAM
CORR_EIT
CORR_GAC
CORR_GAM
CORR_ITC
CORR_LDT
CORR_LHT
Create script (quotes)  with following command and give execute permission to user.

sed -e “s/^/’/g” -e “s/$/’,/” $1|awk ‘{printf (“%s”,$0)}’|sed -e “s/^/(/g” -e “s/,$/)/g”
open t.lst in vi and type :%!quotes
('BANK005','BJSTM','BJS_ORG','CHAINED_ROWS','CORR_BAM','CORR_CAM','CORR_EIT','CORR_GAC','CORR_GAM','CORR_ITC','CORR_LDT','CORR_LHT')

Similarly if you wish to remove blank lines, have a file blank like

awk ‘!NF==0 {print $0}’ $1
Blank lines can also be directly removed from vi using :g/^$/d
Isn’t it cool.. 🙂
2 July, 2009 by Unix 3

Input is too long (> 2499 characters) – line ignored

There are times when you observe above mentioned error while creating view and mview from mview definition taken from Toad or indexfile option. vi editor comes in handy to resolve this issue. Copy the code in Text file and while in escape mode enter following command

:%s/,/,^M/g

Please note that to insert ^M you need to press Ctrl+V+M keys together.We are basically using the command to enter a line break after each comma. 

30 January, 2009 by Unix 0

Disclaimer!!

This blog reflect our own views and do not necessarily represent the views of our current or previous employers.

The contents of this blog are from our experience, you may use at your own risk, however you are strongly advised to cross reference with Product documentation and test before deploying to production environments.

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