resgu (Range Expect Script Generator Utility)

Synopsis:

If you don't have an enterprise level automation software available such as Ansible, but have a need to automate a repetetive ssh or sftp task for tens, hundreds or even thousands of servers without creating an expect script everytime you have a new task to do, then give resgu a try. Resgu is a utility which allows for a single string (or huge one liner) to be sent via ssh or sftp to a range of ip addresses based off a specified host file (sorry ftp is not included due to security issues with the protocol). Great for Linux or AIX administrators and networking administrators that need to get a quick job done fast at a lot of hosts or routers.

Features:

1. Interactive prompts make expect script generation and simultaneous execution for a range of hosts very easy. Just answer the questions and let the utility do all the work. No coding or scripting knowledge required!
2. Allows for up to 7 expect scripts to be simultaneously generated and executed on the fly.
3. Do any single command (or huge one liner) SSH task remotely to as many servers as you want. (sudo included if password is not required for the sudo command).
4. Allows for remote script execution via ssh.
5. GET or PUT files or directories from a range of hosts at once via sftp.
6. Use different hosts files for different environments or cases. Can be handy if you only want to do a task a some of your stores, but they aren't in sequential order of your main hosts file.
7. Execute tasks for a specified range of hosts wthin one of your hosts files.
8. Specify an expect script timeout for the individual connections.
9. Ctrl + C kill switch cleans up afterwards. (Does not change anything on remote servers. Kills local resgu processes and cleans up resgu temp files.)
10. Handles creation of initial login keys.
11. Securely handles passwordless or password required cases via Users file.
12. Handles various AIX or Linux flavors ssh prompts.
13. Minimal configuration to get up and running.

The utility generates and executes multiple expect scripts on the fly and simultaneously based off the user's interactively inputted criteria. The execution of the utility has been tested via SLES 9 through 11, Cent OS 7 and AIX 5, but should also work for systems that utilize other versions of Linux, Unix or Cygwin (assuming you have both a bash shell and expect installed on the local system). The utility is written in bash and expect so feel free to make your own alterations.

Important Notes:

1. This is an extremely powerful utility with very constructive or destructive capabilites depending on who's using it! Upon execution of the utility make sure that you quadrupal check your answers to the interactive prompts.

2. This utility requires both bash (aka bourne again shell) and expect to be installed. I've tested various versions of each without issue, but make no guarantees if the version of bash or expect that you're using cause the utility to fail.

3. Also, the utility will only be able to reach your target hosts if you either have passwordless authentication setup for all target hosts or all of the target hosts logins use the same password. I highly recommend the former where possible.

4. Any user can use the utility (sudo not needed so only give this to users that can be trusted).

5. Make sure your Users and hosts files do not have any blank lines or duplicate entries in them.

6. Files obtained using get will be placed in a specific folder directly under the resgu directory with the name of the remote server it was pulled from.

7. Host names should not included reserved words. Additionally they should not use the word host or test in their hostname.

Initial Setup:

1. Placing resgu and the required files in the appropriate directory
   The resgu executable can only be executed from a users home/user/resgu directory. For instance if I'm logging into the central server as the user "someuser1", then the resgu executable and it's required files must be in the "/home/someuser1/resgu" directory.

2. Setting up the "Users" file
   A file called "Users" must be placed in the directory where resgu executable is. Resgu uses this to tell if the remote user is already setup up with passwordless authentication or not. If not you will be prompted to enter a password. First column is the name of the user and the second column should be set to either passwordnotrequired or passwordrequired accordingly.
   someuser1 passwordnotrequired
   someuser2 passwordrequired
   ansibletower passwordrequired
   root passwordrequired

3. Setting up a single or multiple hosts files
   One or more hosts files named whatever you'd like must be placed in the directory where the resgu executable is. Resgu uses this to connect to the remote hosts via a range that you select interactively upon execution of the utility. Hosts files must be in a two column format just like a normal hosts file.
   server1 12.34.56.78
   server2 12.45.67.89
   server3 13.56.78.89

Usage:

From your user's resgu directory type the below command to start the utility.
./resgu

When you execute the utility you will be greeted with the following warning information that is relevant to the setup and responses you will be providing before the ultimate execution of the expect scripts.

Please answer the following questions appropriately.

1. Users file must be in the following format. someuser1 passwordnotrequired
   someuser2 passwordrequired
   someuser3 passwordrequired

2. Hosts files must be in a two column format.

3. Input commands carefully and with case sensitivity in mind.

4. When using a command string that calls a variable at the remote hosts (uses a $ sign) be sure to double backslash before the character like so:
   ps -ef | grep process | awk '{print \\$2}'

5. Press Ctrl+C to abort.

Interactive prompts (with examples):

1. First enter the name of one of your hosts files.
   testhostsfile

2. Next enter the first host of your range in your selected hosts file.
   server1

3. Next enter the last host of your range in your selected hosts file.
   server1000

4. Next enter the username of your desired remote login.
   someuser1

5. Next enter the password for the user if the user requires a password to login rather than using passwordless authentication (password will not appear on the screen).

6. Next select 1 for sftp or 2 for ssh.
   2

7. Next enter the command to be executed.
   put somefile somewhere

8. Select between 1 and 23 to choose the length of your timeout in seconds (example is for 30 minutes).
   2

9. Select between 1 and 7 to choose the amount of connections to be established simultaneously.
   7

Logging:

To check the progress of the utility you can open a new command line interface and view the templog files under the /tmp directory. How many templogs there are depends on how many simultaneous connections you chose to have. If there are 7 then there will be a file at /tmp/templog1, /tmp/templog2 and so on until /tmp/templog7.

Final log file
Once the utility has finished, then a log file while be generated in the same directory as where the resgu executable was. The log file will be called job(DATE).log. For example if today is December 25th 2018, then the log file will be called job12252018.log. I highly recommend that you check out the log file after execution to make sure the utility does exactly what you wanted. If you run it more than once in a day, then the log will be appended to for that day.