How to switch user for a resource

Chef Infra (archive)
1

If we are doing Oracle Installation via CHEF . The resource needs to run via oracle but the user has logged in as root user.

How to switch user from root to oracle such that complete resource runs via oracle.

bash ‘xxxxx’ do
cwd abcd
code <<-EOH
sqlplus -v > /oracle/local/log/softwareversion.txt
df -h > /oracle/local/log/serverspace.txt
free -g > /oracle/local/log/memoryspace.txt
EOH
end

This bash resource needs to run via oracle user…
how to modify the code to switch user.

this is the method i am using but i need some other option to do so such that complete resource gets executed as oracle user.

#logs for space and memory availability
bash ‘xxxx’ do
cwd aaaa
code <<-EOH
su - oracle -c "sqlplus -v > /oracle/local/log/softwareversion.txt"
su - oracle -c "df -h > /oracle/local/log/serverspace.txt"
su - oracle -c "free -g > /oracle/local/log/memoryspace.txt"
EOH
end

When the recipe runs on node it shows some error like this

bash[xxxxx] action run
[execute] stty: standard input: Invalid argument
stty: standard input: Invalid argument
stty: standard input: Invalid argument
stty: standard input: Invalid argument
stty: standard input: Invalid argument

2

Use the user property in the bash resource

https://docs.chef.io/resource_bash.html

bash 'name' do
  code                       String
  creates                    String
  cwd                        String
  environment                Hash
  flags                      String
  group                      String, Integer
  notifies                   # see description
  path                       Array
  provider                   Chef::Provider::Script::Bash
  returns                    Integer, Array
  subscribes                 # see description
  timeout                    Integer, Float
  user                       String, Integer
  umask                      String, Integer
  action                     Symbol # defaults to :run if not specified
end
3

this user ‘oracle’ is not working in my case.

4

Please provide detailed error information. If possible also the code you executed

5

Is there a way that it is logging in i.e. switching in as oracle user but its not making the logon scripts to be active.

In my case i want a substitute of su - oracle but i think this user oracle is only the replacement of su oracle

6

the error i mean to say is the complete path is not recognized and the file where it is present is not readable

7

Try the path and/or environment parameters in this same resource.
Also you could play with the execute resource
https://docs.chef.io/resource_execute.html

8

execute resource has a constraint that only one command can be fired via one execute resource.

9

where i am using execute resource… i have used su - oracle for that
but with bash i am writing su - oracle for each and every command inside bash resource as mentioned above
code <<-EOH
su - oracle -c "sqlplus -v > /oracle/local/log/softwareversion.txt"
su - oracle -c "df -h > /oracle/local/log/serverspace.txt"
su - oracle -c "free -g > /oracle/local/log/memoryspace.txt"
EOH

and can you tell how can i remove this error

stty: standard input: Invalid argument
stty: standard input: Invalid argument
stty: standard input: Invalid argument
stty: standard input: Invalid argument

10

#logs for space and memory availability
base = node[‘testcookbook’][‘ora_base’]

bash ‘check_space’ do
code <<-EOH
echo $USER > /tmp/env.lst
EOH
user 'oracle’
group 'dba’
end

Now this should give user as oracle but the result is root which means that user property of bash resource is not moving to oracle.
is it a bug??
because instead of using this if we use su - oracle -c “command” then it works fine

11

it is unable to switch to user, seems it doesn’t have permission to do this.

Can you change the log-level to DEBUG and run the recipe again. then check if you can see any error or post it here.

12

How to do that… how to change log level to debug mode

13

That “echo $user” command is not really proof of which user is running - it simply takes whatever is stored in the environment variable. I would assume that the bash resource inherits the environment from the chef run (much akin to what happens when you use “su oracle” rather than “su - oracle”).

If you really want to test, do this:

bash ‘test_root’ do
code <<-EOH
cat /root/.bashrc >/tmp/env.lst
EOH
user 'oracle’
group 'dba’
end

You should get a permission denied if this runs as user oracle, or success if it runs as user root.

Kevin Keane
Whom the IT Pros Call