HPC_Tips:
HPC_Tips is a database for short tips to help HPC users. This tool consists of several parts:
(1) A program, showTips, is installed on login nodes which typically prints a random tip from the HPC_Tips database.
(2) A couple of files containing short tips each being 1 to 5 lines long.
(3) A python program to load the database from supplied list of tips
(4) Tools to setup the configuration file and build and install the necessary programs.
This works by installing a MySQL database on a server which is accessible from all your login nodes. The source for this project can live anywhere. One uses the "load_tips.py" script to install the tips in the database. You place the source on a host where you have write access to the database. If you only allow write access to the database on the server, then the source will have to live there.
Note that the tips database is independent of the install of the showTips program used to display tips to users. Tips can be updated at anytime.
Security Issues:
In order for a user to access the MySQL database, they must have a MySQL account and password. All users use the same account and password that is hardcoded into the showTips binary. A determined user might be able to decode the showTips binary to exact the MySQL account and password. However this account and password only have "select" privileges. They cannot delete or modify the database in any way.
The python script and MySQL username and password that can change the database need to be stored in a location where users cannot access such as the server where the database is stored.
Runtime issues
Since this showTips program is part of the login procedure, it shouldn't hang if the database cannot be accessed. The program has 0.4 second timeout if the database cannot be accessed and no warnings are produced unless requested.
To install:
- Setup MySQL Database:
Have a server which can be seen on the network from your login nodes. On that server install a mysql database server and allow your login nodes access to the the mysql ports on this server. This might require opening ports in various firewalls. For the purposes of this discussion, lets assume that this server is called "alice".
Once this mysql database server is running you'll need to create two accounts to access this database. Here we use "tipBuilder" as the account name that has write access to the database and set "test623" as the password. A second account (account: readerOfTips, pw: tipReader123) is needed to read the tips. You need to login to the mysql program and do:
mysql> create database HPC_Tips;
mysql> create user 'tipBuilder'@'%' identified by 'test623';
mysql> create user 'tipBuilder'@'localhost' identified by 'test623';
mysql> create user 'readerOfTips'@'%' identified by 'tipReader123';
mysql> create user 'readerOfTips'@'localhost' identified by 'tipReader123';
mysql> grant all privileges ON HPC_Tips.* TO 'tipBuilder'@'localhost';
mysql> grant all privileges ON HPC_Tips.* TO 'tipBuilder'@'%';
mysql> grant select ON HPC_Tips.* TO 'readerOfTips'@'localhost';
mysql> grant select ON HPC_Tips.* TO 'readerOfTips'@'%';
mysql> flush privileges;
Obviously, you can use any names and password you like, you just need to be consistent throughout this process.
You may have to edit the mysql.cnf file to allow access. Check here for more details: https://linuxize.com/post/mysql-remote-access/
- Create database config file:
The following program will create a database configuration file used by the load_tips.py program
$ ./conf_create.py
Database host: alice
Database user: tipBuilder
Database pass: test623
Database name: HPC_Tips
If you want to just load the database from the server then replace "alice" with "localhost". This program will use the database name you used to create a file. In this case it will use "HPC_Tips_db.conf".
- Edit tips
The tips directory contains text files are broken into two files. The first is a file called general.tips which contains general tips that should be useful at all sites. The second file called tacc.tips. This file contains tips that probably only make sense at TACC. Many of these can probably be reworded to work for your site. Consider either editting this file immediately or move it out of the way until it contains tips that work for your site.
The following rules are used with the tips:
a) All tips are between lines "##---" as shown below:
##----
It usually takes 30 minutes or more for new passwords to propagate across TACC systems.
##----
b) Long lines are filled to fit the line width on the terminal.
c) Newlines are honored when formatting the tip for the terminal.
d) Leading blanks are honored when formatting the tip for the terminal.
- Load the database:
The load_tips.py program reads the tips/*.tips into the database.
./load_tips.py HPC_Tips_db.conf
Note that the load_tips.py program uses the first argument given as the name of the config file. If no argument is given it tries either "HPC_Tips_db.conf" or "HPCTips_db.conf"
- Check that you can access the database:
Please try to access the mysql database from the login nodes where "alice" is the name of the database server.
$ mysql -u readerOfTips -h alice -p HPC_Tips
Enter password:
mysql> select * from tips limit 1;
If this doesn't work then check to see that you can read the tips on the server by using the mysql command. Then check the firewall rules to allow the mysql ports access to the "alice" server.
- Build the showTips program:
Please configure and make install the showTips binary:
$ ./configure --prefix=/path/to/HPCTips --with-host=alice --with-reader=readerOfTips --with-pass=tipReader123 --with-db=HPC_Tips --with-module=HPC_Tips
$ make install
- Test showTips program
You can test the various options to the showTips binary:
$ /path/to/HPCTips/bin/showTips -n 1
$ /path/to/HPCTips/bin/showTips -w
$ /path/to/HPCTips/bin/showTips -a
$ /path/to/HPCTips/bin/showTips -c
$ /path/to/HPCTips/bin/showTips -h
Where -n # prints a particular tip, -w disables any warning, -a prints all tips, -c reports the configuration and -h prints the help message.
- Install showTips program and the HPC_Tips modulefile on your system
At TACC, we install the showTips program in /opt/apps/HPC_Tips/version/bin/showTip. Then in the /opt/apps/HPC_Tips directory we make a symbolic link between the version and HPC_Tips sub-directory. This way we have a fixed location for the showTips binary. This makes the next step easier.
A copy of our module file can be found in modules/HPC_Tips.lua
- Add the files init/z99_HPC_Tips.sh and init/z99_HPC_Tips.csh to your /etc/profile.d directory for all login nodes
You will need to specify the location of the showTips binary in each of the /etc/profile.d/z99_HPC_Tips.* files to make it work on your system.