Harvard Computer Society (HCS) offers two free web services available to Harvard affiliates: mailing lists and web accounts.

Mailing lists provide an efficient way to facilitate announcements to or discussion among student groups, houses, study groups, blockmates, or groups of friends. It is easy to add any number of Harvard and non-Harvard addresses to a mailing list, and administering them is simple and requires little technical expertise. They have the form list-name@hcs.harvard.edu, and can be created here.

Web accounts are a simple way for any Harvard student group, official or unofficial, to host webpages with a few hundred MB of space, mysql database, and a group-name@hcs.harvard.edu mailing address. The websites are hosted at http://www.hcs.harvard.edu/group-name, and can be requested here.

Yes. Rails is a bit complex, but we're working on making it easy. In general, you should ask us if you need something - we're very friendly.

HCS projects are as diverse as our members: working with the university to better technology policy, managing and securing a production web server, talking about computer science problems, building and destroying computers, etc. A more complete list can be found on our About page.

The best way to get a sense of our projects is to stop by a meeting. We meet weekly in the Student Activity Center at Hilles (SOCH 307) on Wednesdays starting at 8 and running late into the evening.

A complete tutorial is available on how to get into your HCS account for the first time.

Unix (including Macs): type
ssh Your-FAS-Username@fas.harvard.edu
into a terminal prompt ("Terminal" on Macs) and enter your FAS password.
Say yes to any questions about authentication.

Windows: download SecureCRT from here and connect to fas.harvard.edu with your FAS username and password.

Then: From the fas% prompt, type
ssh your-group-name@hcs.harvard.edu
(note the hcs (that's us!) in place of the fas above)
If you are on the access list for the group, you should get a prompt at your group account (something like hera:~>), and if you aren't you will be asked for a password, which you won't know (we only provide access through FAS or with SSH keys).

You probably don't have one! Passwords set with sftppasswd are reset each morning at 4am. We regulate access to our accounts with access lists instead. To get into your account you need to be on this access list, in which case you won't be asked for a password. Other people on the access list can add you-- see "How do I add/remove somebody from the group's access list?" below.

Log in to your group account, and type access. You'll want to use option B for people with fas accounts and option E for everyone else.

We authenticate non-fas users via RSA/DSA keys. You can generate a public/private key pair as follows:

Unix (including Macs): type
ssh-keygen -t dsa
into a terminal prompt ("Terminal" on Macs), and it will run you through the process (selecting the default settings/values is fine). The OpenSSH keyfile, also known as the public key, is the long string of random characters that gets printed to the screen at the end (also found by default at ./.ssh/id_dsa.pub)

Windows: SecureCRT can do it, under Tools>Create Public Key...

Not sure how to make this work? We now have an in-depth tutorial on setting up OpenSSH keys with your HCS account.

http://lists.hcs.harvard.edu/mailman/listinfo/LIST-NAME

http://lists.hcs.harvard.edu/mailman/admin/LIST-NAME
contains every list setting you could ever dream of.

Yes! You should e-mail us to set this up (one day soon it will be automated and you can do it yourself). Meanwhile, you should stake your claim in the DNS namespace by going to your favorite registrar (we can't recommend a particular one, but we can tell you what people have used in the past), spending <$10 for your name (for at least a year, maybe more). You'll have to tell your registrar to set your name to be an alias (CNAME) for artemis.hcs.harvard.edu. Then we'll set it up so that your site magically appears at your domain name. Amazing!

Faulty permissions can cause lots of trouble!

If permissions are set too low, you will get 403 Forbidden errors when loading pages; if they're set too high a hacker may be able to rewrite anything on your site at will. To fix permissions on your account, SSH into HCS and enter these commands

chmod 711 ~ #Fixes perms on your home directory
chmod 711 ~/web/ #Fixes perms on your web directory
chmod -R ugo+r ~/web/ #Sets read bit for everyone on everything in web directory
chmod -R go-w ~/web/ #Prevents others from writing anywhere your web directory
chmod -R u+w ~/web/ #Allows you to write to anything in your web directory

This should prevent others from writing to your files, although insecure PHP code can still be used to hose your website with spam. But for now, if you're new to PHP and Ruby on Rails, try to only use well-maintained and well-known packages like Wordpress or Drupal, follow their instructions carefully, and keep your code up-to-date.

First, HCS runs a useful tool called phpMyAdmin at https://www.hcs.harvard.edu/phpmyadmin/. You can view and modify many of your database settings here. You can also access your mySQL database from the command line by typing

mysql -h mysql.hcs.harvard.edu -u group-name_here --password=sql_password_here

at the command prompt.

Some settings you would use in connecting to the database in a php script:
DB = group_name
DBUSER = group_name (same)
DBPASS = your_mysql_password
DBSERVER = mysql.hcs.harvard.edu

Since the spring of 2005, HCS home directory data has been stored on a network appliance filer, courtesy of a very generous alum. A network appliance filer, for those of you who don't keep track of such things, is a fancy computer with some really big hard disks and a bunch of nify features, designed to make things like storing home directories safer and more convenient. Among the great bells and whistles include snapshot directories: every hour, every night, and every week, the filer takes a "picture" of your home directory and stores it somewhere for you to get at in the case of an emergency. To get at your snapshots, type:

ls .snapshot from your home directory. you'll see something like this:

jharvard-hcs@hera:~$ ls .snapshot
hourly.0 nightly.0 weekly.0 weekly.2
hourly.1 nightly.1 weekly.1


The numbers start at 0 for most recent and count up as the snapshots get older. To get the most recent copy of a file called "foo.txt," sit in your home directory and type:

cp .snapshot/hourly.0/foo.txt .

If you need help with this or with anything else, feel free to contact acctserv@hcs with the details of what you're trying to do.