Changes

{{Admon/important|Backup Your Data|These computers are NEVER backed up. Please save all important files on other storage. '''These machines may fail, be removed , be upgraded, or be reinstalled at any time.'''}}

In order to gain access to these computers, you must send an [[SSH]] key to your [[User:Chris Tyler|professor]].Please follow these instructions exactly:

# Copy the public key (<code>id_rsa.pub</code> or <code>id_dsa.pub</code>) to a file named <code>''yourUserId''.pub</code> -- for example, if your Seneca chosen user ID is "jldoe", save the key in the file <code>jldoejdoe.pub</code> using a command such as: <code>cp ~/.ssh/id_rsa.pub ''jldoejdoe''.pub</code># Attach that file to an e-mail message and send it to [mailto:chris.tyler@senecacollege.ca chris.tyler@senecacollege.ca] including with the course code subject line "SPO600Key" somewhere in the subject line.

=== AArch64 ===<!{{Admon/important|Server Changes|The server configurations have changed several times changed --previous mentions of these systems by name may have referred to different hardware. Note that servers may be added or removed as the semester proceeds.}}  ==== AArch64: aarchie ====The first server is an [[ARMv8]] A main AArch64 system is available, known as '''aarchie''' or '''archie'''. This is machine has a lot of weak cores. You can access this system that is currently located inside at the [[EHL]]hostname aarchie.cdot. To connect to this systems; if you're using a command-line ssh system, you have to go through the EHL gateway on port 2200can access aarchie with a command such as this:  ssh ''username''@aarchie.cdot.systems 

If you're using a command-line ssh system, and you are on the Seneca network, you can issue a command such as this=== AArch64:bbetty ===

ssh -p 2200 Another type AArch64 system is available as ''usernamebbetty''@ehl.internalThis machine has a moderate number of low-medium cores.cdotThis is a system that is currently located inside the [[EHL]]. To connect to this system, you have to go through the EHL gateway on port 2200.systems

To connect from outside SenecaIf you're using a command-line ssh system, you can issue a command such as this:

Another AArch64 system similar to bbetty is named ''ccharlie''. This is a system that is currently located inside the [[EHL]]. To connect from outside Seneca:to this system, you have to go through the EHL gateway on port 2205.

If you're using a command-line ssh -p 2201 ''username''@ehl.cdot.systemssystem, you can issue a command such as this:

If youA different AArch64 system is ''israel're using '. This machine has a commandgood number of mid-line ssh level cores. This system, is located outside of the EHL and you are on the Seneca network, you can issue a command such as thisbe reached directly:

ssh -p 2202 ''username''@ehl.internalisrael.cdot.systems

ssh === x86_64: xerxes.internal.cdot.systems===

To connect from outside Seneca:  ssh -p 2201 The x86_64 server system is known as ''usernamexerxes''@ehl.cdot.systemsIf you're using a command-line ssh system, you can access xerxes with a command such as this:

If you're using OpenSSH (the ssh client used on most Linux systems and other platforms), you can simplify complex ssh command lines by placing host connection details in the file <code>~/.ssh/config</code>:

<!-- Host "aarchie" hostname "ehl.cdot.systems" user "YourUserID" port 2200 Host "bettybbetty"

port 22012202

Host "betty-internalccharlie" hostname "ehl.internal.cdot.systems" user "YourUserIdYourUserID" port 22012205

user "YourUserIdYourUserID" port 22022200 Host "ccharlie" hostname "ehl.cdot.systems" user "YourUserID" port 2205 Host "israel" hostname "israel.cdot.systems" user "YourUserID"

Host "xerxes-internal" hostname "ehl.internalxerxes.cdot.systems" user "YourUserIdYourUserID" port 2202

Once you have added these lines (inserting your user ID where appropriate) and set the permission on that file (<code>chmod 0600 ~/.ssh/config</code>) you can use these commands to access betty and xerxes from outside of Senecathe servers:

ssh bettyaarchie ssh bbetty ssh ccharlie ssh israel

Or these commands You can similarly configure simplified access in most other SSH client programs. == SSH Access from Other Client Systems == If you wish to access betty and xerxes the servers from additional computers, you can append the SSH public keys from inside Seneca:those computers to the <code>~/.ssh/authorized_keys</code> file.

{{Admon/caution|Do Not Build or Install Software Except Via RPM (dnf/yum) or DEB (apt)|Do not build or install software as the root user (using <code>sudo</code>), except in RPM or DEB form using the <code>dnf</code>/<code>yum</code> or <code>yumapt</code> commands(as appropriate to the system). Building or installing software as root may overwrite system files and be very difficult to track down.<br /><br />It is OK to install software into your own directories (e.g., <code>~/bin</code> or <code>~/local</code>), which can be done without root privilege.}}

In order to use <code>sudo</code>, you will need to know your password. An initial random password is provided in the file <code>~/password.txt</code> (which is note that your password will be different on each server). Feel free to change this with the <code>passwd</code> command -- not by editing the file, which is provided only for your information.!