Thursday, October 20, 2011
uCertify 117-101 Junior Level Linux Professional-I review
Recently, the folks at uCertify requested I review one of their certification test suites.
In my past experiences with certifications I've used a variety of study material, including instructor led classes, books, as well as electronic tools similar to those offered by uCertify.
I prefer instructor led classes, but a mix of books and electronic tools are also a viable option for me.
The uCertify catalog includes a wide variety of test preparation kits for a number of popular certifications, including: LPIC, Cisco, Zend, Linux, Microsoft, etc. Given I am currently in the process of studying for my LPIC-1, I selected the Junior Level Linux Professional (LPIC-1) track, which provided me access to the 117-101 Junior Level Linux Professional-I preparation kit.
I was able to install the software quickly and easily without any problems. The activation was also painless, which I expected.
To start out, the tool offers a variety of teaching tools including study notes and practice quizzes, which is what I was really looking forward to. Each of the components is easy to use and follow, although the navigation confused me a bit at first.
The content itself seems accurate. Much of it appears to be snippets of relevant text from the official Linux man pages, with some text with a degree less of technical jargon to it to further explain the topic at hand. There where some areas where the content was a little lacking, but it didn't happen too often.
The practice tests themselves are pretty good. They relate directly to the study material and are worded such that they are easy to comprehend. They also have the same cadence and tone that are on the actual tests.
A couple of nice features that stood out from other tools I have used in the past include the ability to select different test modes and creating custom tests. In addition, within the test itself, the ability to add notes, print items and even provide feedback are all quite helpful. Of course, it also contains other expected features such as bookmarking of questions and a summary of answers for final review prior to submitting for results. The test experience itself was quite good and provided simple methods for reviewing the results and furthering one's understanding of the subject.
Without the benefit of having taken the official exam, it is also a bit difficult to gauge the usefulness of other features such as the Test Readiness Report and Objective Readiness Report, both of which are aimed at providing insight as to how well one might perform on the official test.
Overall, the uCertify tool is a comprehensive and flexible learning tool that is definitely worth considering, specially at the $80 - $100 price point (depends on selected test). Those looking for self-paced preparation kits will find it easy to use, thorough and extremely helpful.
TL;DR
Simple installation
Good Price point
Relevant study material
Comprehensive set of tools
Different learning techniques for varying preferences
Flexible practice tests
uCertify test preparation kits are available at: www.ucertify.com
Tuesday, September 27, 2011
System Activity Report (sar) and You
The second cron job runs at 23:53. This cron job summarizes the days activity. Both of the reports are saved as binary data, so normal tools are useless here.
There are many flags to use with sar when running it interactivly. Some of the flags have additional atguments that are required when used. One example of thses flags is -n which al requires an additional argement suach as DEV or NFS ro IP. This specific example has eightteen (18) potential arguments, not including ALL.
With sar liberal use of the man pages are highly suggested. Not only are the flags and any arguments documented, but the headers for each one and what they represent are explained as well. This comes in handy if you get overzealous with flags and aren't quite sure what you're looking at.
I'm only going to cover some of the most notable flags, what they show and their headers. Be careful however as some flags exist in both upper and lower case and report vastly different metrics. One example of the is -b which reports on I/O transfer but -B reports on paging stats.
First off the plate is -b which as I've already stated reports on I/O transfer stats and has the following headers:
tps: Transfers per second to a physical device.
rtps: Read transfers per second to a physical device.
wtps: Write transfers per second to a physical device.
bread/s: Blocks (since kernel 2.4 = sectors = 512 bytes) read from devices per second.
bwrtn/s: Blocks written to devices per second.
Example output from a production server running: sar -b 1 1
Linux 2.6.18-274 el5PAE (server.domain.com) 8/26/2011
09:23:57 PM tps rtps wtps bread/s bwrtn/s
09:23:58 PM 7829.00 133.00 7696.00 1528.00 76960.00
Average: 7829.00 133.00 7696.00 1528.00 76960.00
-B will report paging stats. Some metrics / headers are only available in kernels 2.5 and newer.
pgpgin/s: Kilobytes paged in from disk per second.
pgpgout/s: Kilobytes paged out from disk per second.
magflt/s: Major faults per second (hits to disk, this is a bad thing...)
-c Process creation stats.
proc/s: Processes created per second.
-d Activity for each block device.
tps: Transfers per second
rd_sec/s: Sectors (512 bytes) read from block device per second.
wr_sec/s: Sectors (512 bytes) written to block device per second.
avgrq-sz: Average # of sectors
avgqu-sz: Average queue length
await: Average time in milliseconds for queue + servicing request.
svctm: Average servicing time.
%util: CPU percentage while I/O requests where issued. Close to 100% = device saturation.
-n DEV Network interface stats.
IFACE: Interface Name
rxpck/s: Packets received per second.
tcpck/s: Packets sent per second.
rxbyt/s: Bytes received per second.
txbyt/s: Bytes sent per second.
rxcmp/s: Compressed packets received per second.
txcmp/s: Compressed packets sent per second.
rxmcst/s: Multicast packets received per second.
-P ALL Per processor (or core) stats
-p Print pretty device names
Shows block devices as sda instead of dev8-0. Has no effect on Network device names.
-A same as: -bBcdqrRuvwWy -I SUM -I XALL -n ALL -P ALL
After you install the sysstat package you really need to let it run for a while and gather stats to see the real beauty of it all. However you can run it interactively if required. When running sar interactively the syntax is sar -FLAGS Interval Duration. (e.g. sar -b 2 60) runs I/O stats every two seconds for a minute. This is very hand to run if you're troubleshooting a slow system or watching it under load.
Monday, October 04, 2010
Enabling the Administrator user in Windows 7
- Open up a command prompt as Administrator (not the same thing we are trying to do)
- Run "net user /active:yes administrator"
- Now it is a great idea to set a password for the Administrator user so we can do that right now
- Run "net user administrator password" but replace password with something more complex similar to "Som3C0mpl3xP@$$w0rd"
- Exit out of the command prompt.
Wednesday, February 10, 2010
Mounting a LVM volume in Ubuntu (Live CD)
Upgrading the Firmware on a 3com 4500 switch
Friday, September 11, 2009
Bash: Finding files between two dates in the current directory
find . -type f -exec ls -l --time-style=full-iso {} \; | awk '{print $6,$NF}' | awk '{gsub(/-/,"",$1);print}' | awk '$1>= 20071019 && $1<= 20071121 {print $2}'find *.pgp -type f -exec ls -l --time-style=full-iso {} \; | awk '{print $6,$NF}' | awk '{gsub(/-/,"",$1);print}' | awk '$1>= 20071019 && $1<= 20071121 {print $2}'find *.pgp -type f -exec ls -lh --time-style=full-iso {} \; | awk '{print $6,$NF,$5}' | awk '{gsub(/-/,"",$1);print}' | awk '$1>= 20090624 && $1<= 20090901 {print $2,$3}'Howto Make a T1 Crossover Cable
I learned this one about a month ago while turning up the T1 connection for my fax server. The tech that installed the Cisco equipment left us with a crossover cable, but a data one, so I cut the ends off and re-crimped the cable like so:
You only have to worry about 4 of the 8 wires if you are using typical cat-5 cable like I did.
1 <—> 4
2 <—> 5
4 <—> 1
5 <—> 2
Or if you go by colors like I do
Side 1 (left is cable end, clip underneath):
Pin 1: Orange White
Pin 2: Orange Solid
Pin 3: none
Pin 4: Blue Solid
Pin 5: Blue White
Pin 6: none
Pin 7: none
Pin 8: none
Side 2 (left is cable end, clip underneath):
Pin 1: Blue Solid
Pin 2: Blue White
Pin 3: none
Pin 4: Orange White
Pin 5: Orange Solid
Pin 6: none
Pin 7: none
Pin 8: none
Then you are done!
Friday, July 10, 2009
Creating a RAID 5 Array in software on CentOS 5.3
Tuesday, July 07, 2009
Copy Directory Structure Only
Wednesday, May 27, 2009
Failed to modify password entry for user while adding user with smbpasswd
I read over the man pages for smbpasswd and saw that I needed to add the -n switch because this user will not have a password. So again I tried to add the user with "smbpasswd -a -n [USER]" and got the same error.
A quick Google search lead me to a newb mistake on my part... I didn't have the user I was trying to add in my UNIX password file. A quick "useradd [USER]" followed by the same "smbpasswd -a -n [USER]" and I was all set.
Granted there are other reasons why this process might fail, but for me this was the reason.
Friday, January 23, 2009
Things learned over time, Part 1
Monday, March 10, 2008
uCertify Test Engine Review
The download and installation of the product was straight forward. They even offer you a chance to do some practice tests for free to test out the software. The test itself is inexpensive coming in at $49.99 for a single user. Not bad in my opinion. So far I have only gone through the 15 question diagnostic test once, but the questions where challenging none the less.
I will be using this practice test for my 70-284 exam to truely test it out and to be honest I think it will work. I have to go through all of the exams first and then start using the "Adaptive Test" to really hone in on areas I have trouble in. Also the custom test allows you to pick areas of the exam that you are really struggeling with so you can "turn your weakness into stenght".
Thursday, January 03, 2008
Fixing a bad Master Boot Record (MBR) in Microsoft Vista
Removing those partitions removed GRUB as well, so my laptop (now my main computer) would no longer boot into Microsoft Vista Home Premium. To fix this I used the Vista DVD to boot into Windows Recovery Environment (Windows RE) and used a tool new to me Bootrec.exe.
Microsoft has a very handy article on how to use Bootrec.exe to fix just such an occasion. For my situation I had to use the /fixMBR switch and reboot. It was literally that simple!
Friday, November 09, 2007
Handy Microsoft related blogs
Port 25 The Open Source Software Lab at Microsoft
Microsoft Exchange Team Blog (You had me at EHLO...)
Microsoft Internet Information Services HomepageAlso if you have sites that you find useful please leave them in the comments so I can addt them.
Thursday, September 27, 2007
Testing Outlook Web Access from the PowerShell
Today I figured out how to do all of this from a PowerShell, which has already cut my daily monitoring duties down about 90%. This is a pretty simple oneliner that will test one OWA url. It does however require you to enter a password in a dialog box.
Test-OWAConnectivity -url https://mail.yourdomain.com/owa -mailboxcredentials:)Get-Credential domail\user)
After you run that it will ask you for the password of the user and report back success or failure.
Tuesday, July 17, 2007
Troubleshooting Tips: RPC over HTTP
Make sure you are using Basic Authentication with the RPC proxy.
Triple check that Outlook Anywhere is enabled on the Microsoft Exchange 2007 server and that the RPC Proxy is installed.
Close Outlook and open it backup with the switch /rpcdiag (Start, Run, Outlook.exe /RPCDIAG).
Also since you are using Basic Authentication you must be using SSL. The SSL certificate must be trusted by the computer that is running Outlook, so I suggest it is a third party certificate that came from a reputable online source. You can only use self-signed certificates if all the computers that will be connecting to Outlook Anywhere are also part of the domain that created them.
Maybe I should do a complete series of how to's in regards to Outlook Anywhere and RPC over HTTP.
Wednesday, July 11, 2007
Microsoft Exchange 2007 Distribution Group Security
With this setting on users outside your company cannot email to the distribution group. For some of my groups this is what I want. But for specific groups I want people outside my enterprise to be able to send them email.
To change this setting open up the "Exchange System Console" and go to the Recipient Configuration, Distribution Group. Then right click on the distribution group you wish to edit and choose properties. Next click the "Mail Flow Settings" tab and select the "Message Delivery Restrictions" and then hit the "Properites" button. On the "Message Delivery Restrictions" screen uncheck the "Require that all senders are authenticated" option and you will be all set.
To do all of the above from the "Exchange Management Shell" you can use the one-liner below.
Set-DistributionGroup -identity "DisplayNameOfDistributionGroup" -RequireSenderAuthenticationEnabled $False
It's really that easy.
When I first got my hands on Microsoft Exchange 2007 I did not like the idea of doing alot of things by the command line, but as time goes on I have found out that the Management Shell is a very powerful tool that every Exchange admin should learn how to use and fall in love with.
Tuesday, July 10, 2007
How to: Update the Global Address List in Microsoft Exchange 2007
Update-GlobalAddressList -identity "Default Global Address List"
Thursday, June 14, 2007
Microsoft Exchange TCP/IP Ports List
TCP port 25 - SMTP
TCP port 26 - SSL secured SMTP
TCP port 110 - Post Office Protocol v. 3 (POP3)
TCP port 995 - SSL secured POP3
TCP port 143 - Internet Message Access Protocol v. 4 (IMAP4)
TCP port 993 - SSL secured IMAP4
TCP port 80 - HTTP for Outlook Web Access
TCP port 443 - SSL secured HTTP for Outlook Web Access (HTTPS)
TCP/UDP port 389 - Lightweight Directory Access Protocol (LDAP)
TCP port 3268 - LDAP communications with an Active Directory Global Catalog Server
TCP port 119 - Network News Transfer Protocol (NNTP)
TCP port 563 - SSL secured NNTP
TCP port 135 - Remote Procedure Protocol (RPC) however it will also use ports 1024 and up as needed.
TCP/UDP port 53 - Domain Name System (DNS)
TCP port 102 - Mail Transfer Agent (MTA) *Only used in X.400 connections.
TCP/UDP port 88 - KERBEROS
Additionally if you are secureing any servers such as front-end / back-end servers with IPSEC you will need to allow IP protocol 51 for the Authenitcation Header, IP protocol 50, TCP/UDP port 88 for KERBEROS, and UDP port 500 for Key Exchanges.
That's a pretty decent sized list "JUST" for one network service. On the plus side most of those are not needed in a default setup as POP3 and IMAP4 are rarely used in a pure Microsoft network.
Also hopefully this will help me remember some of the less used ports and let me ace my test!
-EDIT: Thanks to the commenter I updated this post to have the correct Global Catalog server port.
Friday, June 08, 2007
How to Delete the Undeletable File!
Geeks are Sexy has a good article on how to delete pesky undeletable files. I already knew about #1. I always first try to kill "Explorer.exe" from task manager before I do anything drastic. If that doesn't work I move on to number three if I have Unlocker handy.
I typically have either unlocker installed or an Internet connection to download a copy so I have never had to resort to using the Recovery Console on my computer. Also it is far more likely that I would have those then a Windows CD around to use the recovery console as I always forget to install it before hand.