Oracle VM Site Review - Oracle VM Health Check
view counter

Linux Feed

Linux Support, Oracle Linux, Red Hat Enterprise Linux, SUSE, Oracle Unbreakable Enterprise Kernel and the Oracle Unbreakable Linux Support Program (ULN) resources, news, and support articles.

Kibana connection failed elasticsearch 1.4

While trying to setup ELK(Elastic Search, Logstash and Kibana) I got an error saying “Connection Failed”
If you are suing elastic search version 1.4 or above this issue will occur.
To resolve it append following lines in elasticsearch.yml file(which is in config directory of elastic search):

http.cors.allow-origin: "/.*/"
http.cors.enabled: true

After adding above lines restart elasticsearch.
This should fix “Connection Failed” issue.

Picturesque Lock Screen

Picturesque Lock Screen brings the beautiful Bing home page images to your Android lock screen.

Ganglia – rrd remove negative spikes

By using rrdtool tune we can remove negative spikes from any rrd(round robin database).
$ rrdtool tune  --minimum ds-name:min
where, ds-name is the name you will use to reference this particular data source from an RRD.
min is minimum value, if we set minimum value of zero, it prevents negative rates.
In this example I am using test.rrd as my input rrd file.
To get ds-name first extract rrd file and with following command:

Learning command arguments using

Suppose you come across the following command in a script. You are not quite sure what it does. Specifically, you want to know the meaning of each command argument. $ wget --spider -r -nd -nv -H -l 1 -w 2 -o test.log Traditionally, to find out what each argument does, you look up the man page for the wget command. Then, you scroll through page after page of information, and extract the description for each argument. This is a time-consuming, and eye-straining exercise.

Python – find files in directory with extension

The glob module finds all the pathnames matching a specific pattern according to the rules used by the Unix Shell. No tilde expansion is done, but *, ?, and character ranges expressed with [] will be correctly matched.
To list all files ending with *.txt in /home/guest directory:

>>> import glob
>>> glob.glob("/home/guest/*.txt")

[‘/home/guest/syslog.txt’, ‘/home/guest/mysql.txt’, ‘/home/guest/topics.txt’, ‘/home/guest/bus.txt’]

Get 56GB of free cloud storage in one folder!

Dropbox gives you up to 16GB free. Google Drive & Gmail give you 15GB.OneDrive gives you 15GB.Box gives you 10GB.

CVE-2015-0235: Replacing the CloudStack systemvm template

Due to the Ghost bug aka CVE-2015-0235, we had to upgrade 500+ system vm’s. We’re running CloudStack 4.4.2. The version of the systemvm template it uses was 4.4.1 and so we created 4.4.2 and used that instead. It was quite some work to get it done so we thought it was worth sharing how we […]

Username and password with wget/curl

To download a url with basic authentication we need to pass username & password.
To acheive this functionality with wget or curl observer following examples:
With curl:
$ curl -u 'username:password' ''
With wget:
$ wget --user='username' --password='password' ''
Wget with cookie:

Python – remove first and last character

By using slicing technique we can remove first ans last character from a string.
Observe following example for more details:

>>> input = "abcd"
>>> input[1:-1]

In above example I removed a and d from input string (‘abcd’) with input[1:-1], so out our output is ‘bc’.

view counter