I’ve added a Questions and Answers section at http://itadmins.org/qa . Please feel free to post your IT related questions, whether you are looking for advice on a tough job or just have a tech topic you were always curious about. As always, please be courteous to your fellow users!
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I registered #itadmins on freenode.net for discussions about tech realted items. It will serve it’s purpose very soon. Check back often!
I am amazed at the semantics as much as everyone else. The FCC order blocking traffic shaping has been overturned. Does this mark the end of Net Neutrallity? Maybe. In a statement on Broadband.gov , Austin Schlick, General Councel for the FCC, is focused on moving forward with funding broadband in rural areas, while according to RadioInk Magazine, Commissioner Michael Copps may be considering classifying Internet access a telecom service. This would add very aggressive regulations and possibly a Universal Access Fee, in my opinion. I think this may be a way to fund the Broadband initiatives, but I have mixed feelings on it. Comcast has stated that they will continue to cooperate with FCC initiatives, which is a plus for everyone.
dmidecode – DMI table decoder
dmidecode is a tool for dumping a computer’s DMI (some say SMBIOS) table contents in a human-readable format. This table contains a descrip
tion of the system’s hardware components, as well as other useful
pieces of information such as serial numbers and BIOS revision. Thanks
to this table, you can retrieve this information without having to
probe for the actual hardware. While this is a good point in terms of
report speed and safeness, this also makes the presented information
The DMI table doesn’t only describe what the system is currently made
of, it also can report the possible evolutions (such as the fastest
supported CPU or the maximal amount of memory supported).
SMBIOS stands for System Management BIOS, while DMI stands for Desktop
Management Interface. Both standards are tightly related and developed
by the DMTF (Desktop Management Task Force).
As you run it, dmidecode will try to locate the DMI table. If it suc
ceeds, it will then parse this table and display a list of records like
Handle 0x0002, DMI type 2, 8 bytes. Base Board Information
Product Name: C440GX+
Serial Number: INCY92700942
Each record has:
A handle. This is a unique identifier, which allows records to refer
ence each other. For example, processor records usually reference
cache memory records using their handles.
A type. The SMBIOS specification defines different types of elements
a computer can be made of. In this example, the type is 2, which
means that the record contains “Base Board Information”.
A size. Each record has a 4-byte header (2 for the handle, 1 for the
type, 1 for the size), the rest is used by the record data. This
value doesn’t take text strings into account (these are placed at the
end of the record), so the actual length of the record may be (and is
often) greater than the displayed value.
Decoded values. The information presented of course depends on the
type of record. Here, we learn about the board’s manufacturer, model,
version and serial number.
-d, –dev-mem FILE
Read memory from device FILE (default: /dev/mem)
Be less verbose. Unknown, inactive and OEM-specific entries are
not displayed. Meta-data and handle references are hidden. Mutu
ally exclusive with –dump.
-s, –string KEYWORD
Only display the value of the DMI string identified by KEYWORD.
KEYWORD must be a keyword from the following list: bios-vendor,
bios-version, bios-release-date, system-manufacturer, system-
product-name, system-version, system-serial-number, system-uuid,
baseboard-manufacturer, baseboard-product-name, baseboard-ver
sion, baseboard-serial-number, baseboard-asset-tag, chassis-man
ufacturer, chassis-type, chassis-version, chassis-serial-number,
chassis-asset-tag, processor-family, processor-manufacturer,
processor-version, processor-frequency. Each keyword corre
sponds to a given DMI type and a given offset within this entry
type. Not all strings may be meaningful or even defined on all
systems. Some keywords may return more than one result on some
systems (e.g. processor-version on a multi-processor system).
If KEYWORD is not provided or not valid, a list of all valid
keywords is printed and dmidecode exits with an error. This
option cannot be used more than once, and implies –quiet.
Mutually exclusive with –type and –dump.
-t, –type TYPE
Only display the entries of type TYPE. TYPE can be either a DMI
type number, or a comma-separated list of type numbers, or a
keyword from the following list: bios, system, baseboard, chas
sis, processor, memory, cache, connector, slot. Refer to the DMI
TYPES section below for details. If this option is used more
than once, the set of displayed entries will be the union of all
the given types. If TYPE is not provided or not valid, a list
of all valid keywords is printed and dmidecode exits with an
error. Mutually exclusive with –string.
Do not decode the entries, dump their contents as hexadecimal
instead. Note that this is still a text output, no binary data
will be thrown upon you. The strings attached to each entry are
displayed as both hexadecimal and ASCII. This option is mainly
useful for debugging. Mutually exclusive with –quiet and
Display usage information and exit
Display the version and exit
The SMBIOS specification defines the following DMI types:
2 Base Board
5 Memory Controller
6 Memory Module
8 Port Connector
9 System Slots
10 On Board Devices
11 OEM Strings
12 System Configuration Options
13 BIOS Language
14 Group Associations
15 System Event Log
16 Physical Memory Array
17 Memory Device
18 32-bit Memory Error
19 Memory Array Mapped Address
20 Memory Device Mapped Address
21 Built-in Pointing Device
22 Portable Battery
23 System Reset
24 Hardware Security
25 System Power Controls
26 Voltage Probe
27 Cooling Device
28 Temperature Probe
29 Electrical Current Probe
30 Out-of-band Remote Access
31 Boot Integrity Services
32 System Boot
33 64-bit Memory Error
34 Management Device
35 Management Device Component
36 Management Device Threshold Data
37 Memory Channel
38 IPMI Device
39 Power Supply
Additionally, type 126 is used for disabled entries and type 127 is an
end-of-table marker. Types 128 to 255 are for OEM-specific data.
dmidecode will display these entries by default, but it can only decode
them when the vendors have contributed documentation or code for them.
Keywords can be used instead of type numbers with –type. Each keyword
is equivalent to a list of type numbers:
bios 0, 13
system 1, 12, 15, 23, 32
baseboard 2, 10
memory 5, 6, 16, 17
Keywords are matched case-insensitively. The following command lines
dmidecode –type 0 –type 13
dmidecode –type 0,13
dmidecode –type bios
dmidecode –type BIOS
More often than not, information contained in the DMI tables is inaccu
rate, incomplete or simply wrong.
Alan Cox, Jean Delvare
biosdecode(8), mem(4), ownership(8), vpddecode(8)
dmidecode February 2007 DMIDECODE(8)
Setting up PXE options on your network can be an ideal choice if you depend on iso files and spend a lot of time testing operating systems. I recently decided to do this on my home network to eliminate the clutter of burning a ton of CDs. This was my logic:
Is this a green solution? It can be if you take into consideration of adding smaller, low-power devices to your network instead of full-blown computers. Two companies I can recommend for the clients are Diskless Workstations and devonIT. The noise reduction factors switching to diskless clients can be amazing. Another option that may have some green factor to it is using that older machine that is sitting in your basement or garage (we all have them) instead of throwing it away. Keep an eye on power consumption if you choose to use older equipment, though.
If you have several independent computers, problems quickly develop. Files become scattered over every machine you touch. Where was that brilliant resume you sent out last month that got such positive response? These random files require an intensely complex backup routine and will be difficult to track. The problem of having different versions of files also comes into play. By keeping it all on one server, you are making things much simpler.
You spend what seems like countless hours updating your systems with the same fixes over and over if you don’t “go thin”. While it is commendable to treat each system with individual attention and know each system, do you really want to spend all your free time updating? This goes along the lines of centralization, but there is a time benefit when you have only one server to upgrade.
Thin Clients are much cheaper. You can expect approximately 350-500 dollars per machine for decent hardware. Configured correctly, the performance of these machines can rival high-end $1000+computers. Touching back on the centralization, some cloud computing backup providers and backup application vendors charge you per computer. It makes so much more sense to have one backup target.
These are the benefits that have made me come to the conclusion to create a PXE environment. I will, of course, move slowly and make sure all the steps are done properly, but the advantages have out weighed other factors at this point.
I’ve been wrestling with a logo for itadmins.org for a long time. I want something that reflects technology, but isn’t too cheesy. These are a couple models I came up with, but I am still not completely satisfied with them. If anyone can offer some insight, it would be much appreciated.
During the course of my ten year career as a technologist, I have come across several sites that help me with day to day problems, expand my knowledge beyond studies, and make the information overload seem a little more structured. Rather than “become the best Googler” it’s sometimes better to be a little more selective in your reference materials. This is a list of sites I have used hundreds of times in the past.
During a traffic audit, it becomes very critical to know exactly what you are looking at. I often refer to this document. A very important consideration to those new to the field: IANA does not enforce these assignments. They are only here to be the official registry. Just because you see a specific port being used, doesn’t absolutley mean that port is carrying it’s assigned traffic. Worms will often use well-known ports to disguise themselves. Rule of thumb: always analyze the packets, don’t just assume based on the port.
The Ubuntu Forums are very valuable as a reference tool. It always helps to read an entire thread before implementing things, due to the assistanceit provides being user-generated content. It saved numerous reinstalls when I first started using Ubuntu.
When I went searching for this site, I was guided to a link informing me that all documentation would be merged to the support site. Clicking on that link, directed me to a redirect to the “New” support site. (kind of Monty Python-ish, I know). Regardless of where it is and what it is called, Cisco has stellar documentation for IOS and all of their products online for brushing up on your skills.
This is the place I go as a darkhorse search of last result for information about open source troubleshooting. It’s not due to a lack of information or quality. Linux Forums has been around for 10+ years and I remember using it intensly to learn about Red Hat and Mandrake Linux. It is still a high traffic site and if I have a question regarding RPM-based distributions, I will still frequent it. The usual warning about reading an entire thread applies here as well. Become an expert, not just someone looking for a quick fix.
The name says it all with this one. Debian has a strong library of resources to learn how to implement solutions and resolve problems in this distribution.
This is the default place I look for domain owner information. It is always handy to have access to this in a situation where your customers are using third party services that provide specialized solutions.
Do you have any suggestions for any other sites that help make your day as an IT Admin? Please feel free to suggest your own favorites in the comments section.
While on my routine stumble-around this morning, I located a coffee table book that is suitable for the technologist in all of us. Call me strange. I get excited about new technology and new ways of doing things, but I also enjoy learning how we got to this age of constant beeps, digitizing everything we used to touch, and having friends all over the world. Core Memory is a collection of very artistic photographs from the Computer History Museum by photographer Mark Richards and author John Alderman capturing computer history and presenting it in a very artful way. This one will definitely be on my coffee table next to my Irish history books and Chicago Architecture books. Click here to check it out on Amazon.
Mark and John discussed this project in 2007 at Google. Here is the video from this event:
With so many people out there looking for a job right now, I thought it would be nice to compile some tips on writing resumes in the technical field. Individual results may vary, but these are a few things I have learned:
1. Always include a Skills section if you are going to post your resume to a form. The reason why you are doing this is to provide a list of searchable skills. If your resume is vague, it will never show up in any queries the company may conduct in the future.
2. Do not under any circumstances whatsoever use a template for your cover letter. Take the time to specifically type out how you qualify for the position, what skills you consider critical to the company’s success, address any gaps between the desired skills and what you know, and make sure it feels like a letter addressed to the company. This brief effort, as simple as writing an email, will get you the attention you deserve. If you apply at the same company twice, using a template twice may make the potential employer question your sincerity.
3. Take notes while on the phone discussing your resume. This will expose any areas you can improve and shore up potential problems. Recruiters and hiring managers are scrutinizing every detail now. If more than one interviewer expresses concern regarding information or you find yourself discussing skills not on your resume often, it is probably time for some editing.
4. Keep multiple file formats on hand. I have a Word, PDF, and text version at all times. There is no data standard for on line job board systems and formatting can take away your dream job in a heartbeat. I upload the Word version, print the PDF version, and copy and paste the Text file. This system seems to fit 99% of the time.
5. Pay very close attention to the job details. The days of blasting out your resume to 200 employers until someone gives you a chance are long gone. There are specific hardware, software, and years of experience requirements that will disqualify you immediately. It is better to assume a quality over quantity position in a finicky job market. You will get more responses and interviewers will be less stressed with everyone. They have very difficult decisions to make and their performance is also being scrutinized.
This is just a brief transfer of my own personal experiences. If you have any others, please feel free to comment.
I really wish there was something we could do about Conficker as a Technology community. There’s a spread of between 3 million and 12 million computers in the world according to CNN. Seems insignificant given the size of the entire Internet. I’d like to pose a question to the community. What tools would we need in order to mitigate the risks of Conficker or any worm for that matter?
Do the normal rules of engagement apply here? When I was in the telecommunications industry, we tackled problems like this systematically:
- Identify the risk.
- Identify the number of infections.
- Allocate all parties and resources necessary to resolve.
- Run hourly checks to ensure every compromised system is attended to.
- “Lessons Learned” with all parties involved once 100% resolution is attained.
Seems like documentation and tracking are the key. At my former company, we used massive spreadsheets and sent updates to those assigned to verify resolution and remove the record. What would scale on the Internet, considering it is between 3 million and 12 million records?
Another question: Should this all be centralized is a consortium? I have mixed feelings with this. In a corporate office it certainly was convenient to have strict policies and standards. Consistent problems bring consistent solutions, as the saying goes. I also consider myself a free market and free Internet kind of technologist.
Perhaps just a crowd-sourced site (I know, I know) focused on the resolution of all the Confickers of the world, providing information, links, etc. would be on the right course. Make it a condition that all the information is Creative Commons and low and behold, maybe we’d have a winner.
Here is CNN’s information regarding recent activity on Conficker. What troubles me about it is the apparent loss of hope in a resolution. Kind of makes me sad to think that Sunday breakfast table conversation might end up starting with Dad opening a newspaper and asking “I wonder what Conficker is up to today?” Very disturbing.
We need to do something about this before it starts to reflect badly on the tech community.