[cs615asa] HW2 graded
jschauma at stevens.edu
Fri Mar 4 21:57:50 EST 2016
I just sent out grades for HW2. If you submitted HW2 and did not
receive a grade, please let me know.
I'm glad to see that most of you did this assignment without too many
problems. A few notes that applied to most, if not all of you:
- text formatting
Please get in the habit of using a unix text editor to write plain ascii
text. Make sure to have it be well formatted and readable. You may
find this post helpful:
- spell check your text
I understand that for many of you English is not your native language.
Please make sure to spell check your text (this also applies _if_
English is your native language). On linux-lab, you can use the
ispell(1) command to spell-check your documents.
- volume availability zone
Many of you noticed that in order to use a volume, it needs to be int he
same availability zone as the instance trying to use it. This hints at
least a little bit at how these volumes are implemented within Amazon.
Try to think about the challenges and possible disadvantages if Amazon
allowed cross-availability-zone volume access.
In order to access a volume, you need to have it 'attached' to an
instance. This is analogous to having a disk drive physically connected
to a system. If you wish to use the same volume on another instance,
you need to detach (unplug) it from the initial one first.
Note: in some cases, it may be possible to access a volume or exported
storage device from a SAN from more than one device. (AWS protects you
against that.) The consequences can be disastrous. Here's an old war
story of mine on this topic:
- creating partitions necessary
When you created a new filesystem on the volume, many did not first
partition the volume. Why was that not necessary? What does this way
about the volumes provided to you by AWS or can this be done on raw disk
space in all cases?
- lessons learned
When the assignment states that you should include some lessons learned,
then I do indeed want you to tell me what you learned or what problems
you overcame. That is often more useful to me to see if you absorbed
the lessons in question than just seeing you execute certain commands.
- sudo file -s
I guess some website somewhere recommends the use of "sudo file -s", but
it's not clear to me why that is helpful (and none of you who used it
explained it). Please make sure that you do not blindly execute
commands that you found on some website somewhere without understanding
what they do or why you should run them.
I don't think I will have the time to grade HW3 before our next class,
but I will send out grades when I do.
In the mean time, please remember to fill out the pre-class survey for
lecture 05 prior to Monday:
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