Quiz 1: Ops 1 (ssh, X11, AWS, opsworks, nginx, Linux)

quiz_1_ops_1

Explain as much as possible what's going on in the following real-world terminal session. 

Guidance:  

Tell us what Linux distros these might be by what their PS1 is or are based off.

What are the vars in each prompt used to produce it?  

In ssh, why did we get an X11 error once and what does -C and -X do?  

How could we be using X11 from an ssh session, anyways?

Given that this is a VPC, what are some tight security group rules that might have allowed these connections?  Why did we use a jumphost?  

What is uswest-2a? (eg, what is uswest, the 2, and the a?)

What commands are we doing automatically to add the keys and where might they live?

Explain the output at the end of cd, each column of the ls output, why we edited nginx, why we touched the file, and the arguments to ps that provided that output.  

How could we have got the pid in the same line as ps execution without having to cat it and type it in again?  

Advanced:  This didn't work.  The pid is not there anymore.  Why?



(9984) [master] sean@Seans-MacBook-Pro:~/code/webserver$ ssh -CX [email protected]
 This instance is managed with AWS OpsWorks.

   ######  OpsWorks Summary  ######
   Operating System: Ubuntu 12.04.4 LTS
   OpsWorks Instance: staging-jumphost
   OpsWorks Instance ID: aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee
   OpsWorks Layers: Jumphost
   OpsWorks Stack: contractor_staging
   EC2 Region: us-west-2
   EC2 Availability Zone: us-west-2a
   EC2 Instance ID: i-XXXXXXXX
   Public IP: XXX.XXX.XXX.XXX
   Private IP: 10.0.0.9
   VPC ID: vpc-XXXXXXXX
   Subnet ID: subnet-XXXXXXXX

 Visit http://aws.amazon.com/opsworks for more information.
Last login: Wed Apr 23 20:19:46 2014 from cpe42.cablecompany.com
Agent pid 21612
Identity added: /home/shoran/.ssh/id_rsa (/home/shoran/.ssh/id_rsa)
Identity added: /home/shoran/.ssh/id_rsa-uswest-2-oregon2-keypair (/home/shoran/.ssh/id_rsa-uswest-2-oregon2-keypair)
(2438) shoran@staging-gateway:~$ ssh -CX [email protected]
X11 forwarding request failed on channel 0
Last login: Wed Apr 23 17:21:00 2014 from 10.0.0.9
[root@ip-10-0-1-249 ~]# cd /opt/nginx/
client_body_temp/ fastcgi_temp/     logs/             sbin/             uwsgi_temp/       
conf/             html/             proxy_temp/       scgi_temp/        
[root@ip-10-0-1-249 ~]# cd /opt/nginx/logs
[root@ip-10-0-1-249 logs]# ls -al
total 1380
drwxr-xr-x.  2 root root   4096 Apr 17 22:59 .
drwxr-xr-x. 11 root root   4096 Apr  3 03:15 ..
-rw-r--r--.  1 root root 703193 Apr 23 19:47 access.log
-rw-r--r--.  1 root root 689398 Apr 23 03:56 error.log
[root@ip-10-0-1-249 logs]# vi ../conf/nginx.conf
[root@ip-10-0-1-249 logs]# touch nginx.pid
[root@ip-10-0-1-249 logs]# service nginx restart
nginx: the configuration file /opt/nginx/conf/nginx.conf syntax is ok
nginx: configuration file /opt/nginx/conf/nginx.conf test is successful
Stopping nginx:                                            [  OK  ]
Starting nginx:                                            [  OK  ]
[root@ip-10-0-1-249 logs]# ls -al
total 1384
drwxr-xr-x.  2 root root   4096 Apr 23 20:33 .
drwxr-xr-x. 11 root root   4096 Apr  3 03:15 ..
-rw-r--r--.  1 root root 703193 Apr 23 19:47 access.log
-rw-r--r--.  1 root root 692024 Apr 23 20:33 error.log
-rw-r--r--.  1 root root      6 Apr 23 20:33 nginx.pid
[root@ip-10-0-1-249 logs]# cat nginx.pid 
20341
[root@ip-10-0-1-249 logs]# ps axuww |grep 20341
root     20341  0.0  0.0  53740  1296 ?        Ss   20:33   0:00 nginx: master process /opt/nginx/sbin/nginx -c /opt/nginx/conf/nginx.conf
root     20357  0.0  0.0 103248   860 pts/2    S+   20:33   0:00 grep 20341
[root@ip-10-0-1-249 logs]#