Monday, June 13, 2016

Beeline HS2 High Availablity Using Zookeeper

Add  Below property in HS2 node and restart the service.
<property>
        <name>hive.server2.support.dynamic.service.discovery</name>
        <value>true</value>
</property>
<property>
        <name>hive.zookeeper.quorum</name>
        <value>node1:5181,node2:5181,node3:5181,node4:5181,node5:5181</value>
</property>
<property>
        <name>hive.server2.zookeeper.namespace</name>
        <value>hiveserver2</value>
</property>

Connecting Hive Via Beeline:

Thursday, February 14, 2013

How to block access to Unix Hidden Directories in Web Clients?

We can block the hidden files and directories in the web-server by adding below config in httpd.conf file.

# The following lines prevent any .files from being viewed by web clients.
<Files ~ "^\.">
Order allow,deny
Deny from all
</Files>

Tuesday, December 4, 2012

How to limit the connection per ip in the server?

We can limit the number of connections per IP on server by installing mod_limitipconn for apache.This will helpfull to control the load in server also.

# cd /usr/local/src

Now, we need to grab the file (this is the latest version as of this post):

# wget http://dominia.org/djao/limit/mod_limitipconn-0.23.tar.bz2

# tar xjvf mod_limitipconn-0.23.tar.bz2

# cd mod_limitipconn-0.23

# apxs -i -a -c mod_limitipconn.c

# cd /etc/httpd/conf

Saturday, December 1, 2012

How to increase the swap filesize in server?

Sometimes, we need to increase the swap file for better performance and procedure as below.

First, Create an 1024MB filesize:

# dd if=/dev/zero of=/swapfile bs=1024 count=1048576

    1. if=/dev/zero : Read from /dev/zero file. /dev/zero is a special file in that provides as many null characters to build storage file called /swapfile.
    2. of=/swapfile : Read from /dev/zero write stoage file to /swapfile.
    3. bs=1024 : Read and write 1024 BYTES bytes at a time.
    4. count=1048576 : Copy only 1048576 BLOCKS input blocks. [ 1024 * 1024MB = 1048576 ]

Make the file as swap filesystem:

# mkswap /swapfile

Set the permission for /swapfile:

# chown root:root /swapfile
# chmod 0600 /swapfile

How to increase the temp partition in linux?

First kill the process which using the tmp directory and backup the tmp directroy.

# cp -prf /tmp /tmp.bak

Unmount the temp:

#umount /tmp

Create an 2GB filesize:


# dd if=/dev/zero of=/usr/tmpDSK bs=1024k count=2048
2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 73.6908 seconds, 29.1 MB/s

# du -sch /usr/tmpDSK
2.1G /usr/tmpDSK
2.1G total

How to install the Multimedia package ( FFmpeg, flvtool2, facc....) in linux server ?

First, we have check whether the GNU C and C++ compilers and other development utilities installed or not. If not then install the utilites of it then only we can proceed to install the multimedia package.

RedHat/Centos: 

# yum groupinstall -y "Development Tools"

Debian/Ubuntu:

#apt-get install build-essential

Dynamic Linked Libraries Path:

Linux uses a system of shared libraries, similar to Windows dlls, for the efficient use of space and resources, and modularity. Add those below entry in  /etc/ld.so.conf

/usr/local/lib
/usr/lib

# ldconfig

Monday, November 12, 2012

Types of Linux FileSystem

Filesystem is an set of files and directories resides in an partition. Linux supports different type of filesystem and details as follow:

   minix     is the filesystem used in the Minix  operating  system,  the
                 first to run under Linux.  It has a number of shortcomings: a
                 64MB  partition  size  limit,  short  filenames,   a   single
                 timestamp,  etc.   It  remains  useful  for  floppies and RAM
                 disks.

     ext       is an elaborate extension of the minix filesystem.   It  has
                 been  completely  superseded  by  the  second  version of the
                 extended filesystem (ext2) and has  been  removed  from  the
                 kernel (in 2.1.21).

    ext2      is  the  high  performance disk filesystem used by Linux for
                 fixed disks as well as removable media.  The second  extended
                 filesystem was designed as an extension of the extended file
                 system (ext).  ext2 offers the best performance (in terms  of
                 speed  and  CPU  usage)  of  the filesystems supported under
                 Linux.

Tuesday, September 18, 2012

How to Amanda Backup Restore?


Amanda backup has can been done by recovery program amrecover, specifying your backup config, host, date, and disk entry. You can then select files with an FTP-like interface.

# amrecover BackupSet1
AMRECOVER Version 2.6.0p2. Contacting server on localhost ...
220 bass AMANDA index server (2.6.0p2) ready.
Setting restore date to today (2008-11-04)
200 Working date set to 2008-11-04.
200 Config set to BackupSet1.
200 Dump host set to bass.foo.com.
Use the setdisk command to choose dump disk to recover
amrecover> sethost bass.foo.com
200 Dump host set to bass.foo.com.
amrecover> setdate 2008-10-14
200 Working date set to 2008-10-14.
amrecover> setdisk /mnt/home8/foobar
200 Disk set to /mnt/home8/foobar.
amrecover> ls