Updated: 2015-01-25 16:54 EST

1 Readings, Assignments, Labs, Tests, and ToDoIndexup to index

1.1 Assignments this weekIndexup to index

Check the due date for each assignment and put a reminder in your agenda, calendar, and digital assistant.

1.1.1 WorksheetsIndexup to index

The worksheets are available in four formats: Open Office (ODT), PDF, HTML, and Text. Only the Open Office format allows you “fill in the blanks” in the worksheet. The PDF format looks good but doesn’t allow you to type into the blanks in the worksheet. The HTML format is crude but useful for quick for viewing online.

Do NOT open the ODT files using any Microsoft products; they will mangle the format and mis-number the questions. Use the free Libre Office or Open Office programs to open these ODT documents. On campus, you can download Libre Office here.

1.2 Lab work this weekIndexup to index

1.3 Upcoming testsIndexup to index

Read the Test Instructions (all the words) before your first midterm test.

  1. First Midterm test: 45 minutes; in class 8am Thursday in Week 6 (February 12)
  2. Second Midterm test: 45 minutes; in class 8am Thursday in Week 9 (March 12)

Tests take place in your 8am lecture hour, not in your lab period.

3 From the Classroom Whiteboard/ChalkboardIndexup to index

4 Real Sysadmin WorkIndexup to index

4.1 Getting locked out of the serverIndexup to index

Your IP address is locked out of the CLS if the connection to the CLS fails before even asking for your login or password. To have the IP address unblocked, contact your instructor.

Someone locks out their home IP from the CLS by trying to log in as user date:

Jan 10 22:24:39 Invalid user date from
Jan 10 22:24:48 Failed password for invalid user date from port 54505 ssh2
Jan 10 22:25:10 Failed password for invalid user date from port 54505 ssh2
Jan 10 22:25:22 Connection closed by [preauth]
Jan 10 22:25:43 refused connect from cpe68b6fcf6cc73-cm68b6fcf6cc70.cpe.net.cable.rogers.com (

4.2 Attacks on the Course Linux ServerIndexup to index

$ fgrep -c "refused connect" /var/log/auth.log

$ fgrep "refused connect" /var/log/auth.log | awk '{print $NF}' | sort | uniq -c | sort -nr | head
   1581 (
    485 (
    187 (
    150 (
    149 (
    144 (
    132 (
    123 (
    117 (
    106 (

$ whois
descr:          CHINANET Hubei province network
descr:          China Telecom
descr:          A12,Xin-Jie-Kou-Wai Street
descr:          Beijing 100088

$ whois
descr:          IP Pool for Iliad-Entreprises Business Hosting Customers
descr:          Online SAS
descr:          Paris, France

$ whois
descr:          China Telecom
descr:          No.31,jingrong street
descr:          Beijing 100032

4.3 Net NeutralityIndexup to index

4.4 Linux NewsIndexup to index

 Take Notes in Class

| Ian! D. Allen  -  idallen@idallen.ca  -  Ottawa, Ontario, Canada
| Home Page: http://idallen.com/   Contact Improv: http://contactimprov.ca/
| College professor (Free/Libre GNU+Linux) at: http://teaching.idallen.com/
| Defend digital freedom:  http://eff.org/  and have fun:  http://fools.ca/

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