Using DSH (Distributed Shell) to Run Linux Command
博客专区 > Jackin 的博客 > 博客详情
Using DSH (Distributed Shell) to Run Linux Command
Jackin 发表于2年前
Using DSH (Distributed Shell) to Run Linux Command
  • 发表于 2年前
  • 阅读 36
  • 收藏 0
  • 点赞 0
  • 评论 0

腾讯云 技术升级10大核心产品年终让利>>>   

摘要: DSH is short for “Distributed Shell” or “Dancer’s Shell” it is freely available on most major distributions of Linux, but can easily be built from source if your distribution does not offer it in its package repository. You can obtain the source at.

DSH is short for “Distributed Shell” or “Dancer’s Shell” it is freely available on most major distributions of Linux, but can easily be built from source if your distribution does not offer it in its package repository. You can obtain the source at.

Install DSH (Distributed Shell) in Linux

We are going to assume a Debian / Ubuntu environment for the scope of this tutorial. If you are using another distribution, please substitute the appropriate commands for your package manager.

On Debian / Ubuntu

First, let’s install the package via apt:

$ sudo apt-get install dsh

On RHEL / CentOS / Fedora

This method is for those who are not using Debian, and want to compile it from source tar balls. First you need to compile “libdshconfig” and install.

# wget http://www.netfort.gr.jp/~dancer/software/downloads/libdshconfig-0.20.10.cvs.1.tar.gz
# tar xfz libdshconfig*.tar.gz 
# cd libdshconfig-*
# ./configure ; make
# make install

Then compile dsh and install.

# wget http://www.netfort.gr.jp/~dancer/software/downloads/dsh-0.22.0.tar.gz
# tar xfz dsh-0.22.0.tar.gz
# cd dsh-*
# ./configure ; make 
# make install

The main configuration file “/etc/dsh/dsh.conf” (For Debian) and “/usr/local/etc/dsh.conf” (for Red Hat) is pretty straightforward, but since rsh is an unencrypted protocol, we are going to use SSH as the remote shell. Using the text editor of your choice, find this line:

remoteshell =rsh

And change it to:

remoteshell =ssh

There are other options you can pass in here, if you choose to do so, and there are plenty of them to find on the dsh man page. For now, we are going to accept the defaults and have a look at the next file, /etc/dsh/machines.list (for Debian).

For Red Hat based systems you need to create a file called “machines.list” in “/usr/local/etc/” directory.

The syntax here is pretty easy. All one has to do is to enter in a machine’s credentials (Hostname, IP Address, or FQDN) one per line.

Note: When accessing more than one machine simultaneously, it would behove you to set up key-based password-less SSH on all of your machines. Not only does this provide ease of access, but security wise, it hardens your machine as well.

My “/etc/dsh/machines.list” or “/usr/local/etc/machines.list” file says:

172.16.25.125
172.16.25.126

Once you have entered in the credentials of the machines you wish to access, let’s run a simple command like uptime to all of the machines.

$ dsh –aM –c uptime
Sample Output
172.16.25.125: 05:11:58 up 40 days, 51 min, 0 users, load average: 0.00, 0.01, 0.05
172.16.25.126: 05:11:47 up 13 days, 38 min, 0 users, load average: 0.00, 0.01, 0.05

So what did this command do?

Pretty simple. First, we ran dsh and passed the “–a” option to it, which says to send the “uptime” command to “ALL” of the machines listed in “/etc/dsh/machines.list“.

Next, we specified the “–M” option, which says to return the “machine name” (specified in “/etc/dsh/machines.list“) along with the output of the uptime command. (Very useful for sorting when running a command on a number of machines.)

The “–c” option stands for “command to be executed” in this case, “uptime“.

DSH can also be configured with groups of machines in the “/etc/dsh/groups/” file, where is a file with a list of machines in the same format as the “/etc/dsh/machines.list” file. When running dsh on a group, specify the groupname after the “-g” option.

For Red Hat based systems you need to create a folder called “groups” in “/usr/local/etc/” directory. In that “groups” directory you create a file called “cluster“.

For example, run the “w” command on all machines listed in the “cluster” group file “/etc/dsh/groups/cluster” or “/usr/local/etc/groups/cluster“.

$ dsh –M –g cluster –c w

DSH provides much more flexibility, and this tutorial only scratches the surface. Aside from executing commands, DSH can be used to transfer files, install software, add routes, and much more.

To a Systems Administrator tasked with the responsibility of a large network, it is invaluable.

共有 人打赏支持
Jackin
粉丝 27
博文 46
码字总数 13191
×
Jackin
如果觉得我的文章对您有用,请随意打赏。您的支持将鼓励我继续创作!
* 金额(元)
¥1 ¥5 ¥10 ¥20 其他金额
打赏人
留言
* 支付类型
微信扫码支付
打赏金额:
已支付成功
打赏金额: