Zedan IT Blog

IT definitions, discussions and more

Recommended Computer Room Temperature & Humidity

Recommended Computer Room Temperature

TempOperating expensive IT computer equipment for extended periods of time at high temperatures greatly reduces reliability, longevity of components and will likely cause unplanned downtime. Maintaining an ambient temperature range of 20° to 24°C is optimal for system reliability. This temperature range provides a safe buffer for equipment to operate in the event of air conditioning or HVAC equipment failure while making it easier to maintain a safe relative humidity level.
It is a generally agreed upon standard in the computer industry that expensive IT equipment should not be operated in a computer room or data center where the ambient room temperature has exceeded 30°C

Recommended Computer Room Humidity

humidityRelative humidity (RH) is defined as the amount of moisture in the air at a given temperature in relation to the maximum amount of moisture the air could hold at the same temperature. In a data center or computer room, maintaining ambient relative humidity levels between 45% and 55% is recommended for optimal performance and reliability.
When relative humidity levels are too high, water condensation can occur which results in hardware corrosion and early system and component failure. If the relative humidity is too low, computer equipment becomes susceptible to electrostatic discharge (ESD) which can cause damage to sensitive components. When monitoring the relative humidity in the data center, we recommend early warning alerts at 40% and 60% relative humidity, with critical alerts at 30% and 70% relative humidity. It is important to remember that the relative humidity is directly related to the current temperature, so monitoring temperature and humidity together is critical. As the value of IT equipment increases, the risk and associated costs can increase exponentially.

Which to use, CAT5 or CAT6 LAN cables?


When you make a new LAN either small or big,  for home or office,  with long distances or relatively short   you may come to a choice between CAT5  or CAT6 cables (Category 5 and Category 6).

CAT5 cables was designed to handle speed of 10/100 Mbps (Fast Ethernet) and it is obsolete and we advise you to not using it, even if you find with low prices.

There is a new enhancement for CAT5 cables which is CAT5e ( ‘e’ stands for enhanced).  This enhanced type can handle speeds of 1000 Mbps (gigabit Ethernet) and designed to reduce crosstalk which means better at keeping signals on different circuits or channels from interfering with each other.

CAT6 cables suitable for speeds up to 10 gigabits Ethernet and even better tackle the issue of crosstalk.   CAT6 cable has an internal separator that isolates pairs from one another.  If you want to “future-proof” your commercial network as much as possible without a significant cost increase, CAT6 is a great choice.

CAT6 cables cost more than CAT5e, and you are building a large network this will be an important factor for cost calculations, and you need to make a proper selection between CAT5e and CAT6.   BUT when you make the selection remember the following:

  • Both types has maximum length of 100 meters
  • If you network mainly depend on applications on the internet, then CAT6 is not the best choice as speeds of download/upload data from the internet these days are limited by tenth of Mbps.
  • There is a considerable difference of cost between CAT5e and CAT6
  • Network devices these days ( and in my believe for some considerable time more ) which are used in business and servers do not exceed speed of a Gbps, and in all residential network do not exceed 10 Mbps,  which means CAT5e is enough.

Conclusion:  in most cases CAT5e is enough, unless you have special requirements and you budget allows.

TMG Reports Empty & Corrupted SQL Logging

I had a problem annoyed me for about two years tat when generating reports in TMG, they were always completed with empty data and graphs and after trying to solve the problem by searching in internet I found (by chance)  that reports will only work if logging in TMG is configured to log to SQL database not text log files.
It was strange and annoying for me as that was not the case when I used ISA 2004 & 2006 before. I always configured ISA logging to text log files so I can use them with other log analysis tools.

So, I have changed the logging back to SQL server (internal SQL Express server) , but surprisingly reports were completed empty as well 😦 . While searching again on the internet for days I found a solution steps to correct problems when logging to SQL server. My problem was similar that it seemed that there was a corruption in the SQL Summary database when I was looking after the problem before and bounce between test and database logging.       The original post from Forefront TMG Product Team Blog: “TMG Logging to LLQ

The solution to my problem was:

1) Listing the databases currently registered in SQL Express server.   From elevated command prompt:
OSQL -E -S .\MSFW -Q “select name from sysdatabases where name like ‘%isalog%'”

tmgimg1I found that there are number of databases registered over a year ago, but they are physically not on my server. As you see in the result of the command, the system cannot find the database files associated with registered database, as explained in the error: “<The system cannot find the file specified.>”.

2)  Then I have dropped all databases by writing command of drop for all databases, then saved them into a text file:

drop database ISALOG_20120527_FWS_000
drop database ISALOG_20120527_WEB_000

3)  Then saved the file as text file named DropDB.sql, then at the elevated command prompt executed the command:
OSQL -E -S .\MSFW -i c:\DropDB.sql


4)  Restarted the “Microsoft Forefront TMG Firewallservice and then check back the Log Status. Then clicked refresh a few times till current status no longer as “Disconnected” but as “Queue in use”.

tmgimg3In my next post I will explain a VB script I wrote to import entries from summary logging database and export them to a single SQL database to analyse them.

Galaxy DUOS second SIM voice call problem during data comnection


I have Galaxy Grand smart phone,  and I like it as it has what I need for mobile connectivity,  suitable screen size in addition to the dual SIM feature.  I use the first SIM card for data connections and voice calls and the second SIM for voice calls.

After I setup every thing and started to use it I noticed a strange problem, that several people told me that when they call me,  they have difficulty to reach me on the second SIM and I started to receive many SMS from the operator informing me that people tried to call me and could not reach me.  At that time I believed that the quality of service that the operator provides is declining!!

But few weeks ago one of my colleagues who use S4 mini ( which is DUOS as well ) that he has the same problem and it seems that the problem when there is a data connection established by the first SIM.   I tried it practically, and I found it TRUE.

It was sad for me 😦 till I found that it is an option in Galaxy DUOS.   In Android 4.x go to SIM Card Manager,  there you will find an option called “Receive incoming calls” unchecked,  check it, and it will tell you that the data connection will be slower,  accept that and the problem will be solved.  For me I did not feel that the data connection, email, web browsing, Facebook, or any of applications like these gone slow.

Recieve Incoming Calls


10 Laws of Software Productivity

Productivity decreased as team sizes increase.

  • LAW 1 – Smaller teams are more efficient: The smaller the team the higher the productivity of each individual person.
  • LAW 2 – SOME schedule compression can be bought: Adding people to a project, to a point, decreases the time and increases the cost.
  • LAW 3 – Every project has a minimum time: There is an incremental person that consumes more energy than he/she produces. Team size beyond this point decreases productivity and increases time. (”Adding staff to a late software project makes it later.”)
  • LAW 4 – Productivity is scalable: Projects of larger software size can use larger teams without violating LAW 3.
  • LAW 5 – Complexity limits staffing: As complexity increases, the number of people that can effectively work on the project and the rate at which they can be added decreases.
  • LAW 6 – Staffing can be optimized: There exists an optimal staffing function that is effectively modeled by the Rayleigh function. Flat (level load) staffing is rarely optimal.
  • LAW 7 – Projects that get behind, stay behind: It is extremely difficult to bring a project that is behind schedule back on plan.
  • LAW 8 – Work expands to fill the available volume: It is possible to allow too much time to complete a project.
  • LAW 9 – Better technology yields higher productivity: More capable teams, better tools, and advanced, stable processes yield higher productivity.
  • LAW 10 – No “silver bullets”: There is no methodology, tool, or process improvement strategy out there that yields revolutionary improvements in project efficiency.

Original Post by:  Dan Galorath — 10 Laws of Software Productivity

Outlook 2010 won’t show pictures in messages

I used to receive HTML messages with embedded pictures but suddenly my outlook 2010 stopped displaying the messages and displays a blank box instead.  That was annoying because I missed many offers and information.

After a long search in forums I found a solution for this (Outlook 2010 case):

1. Click the New Email button or press Ctrl+N while viewing the Inbox.
2. Go to the new message’s File, Options dialog (in the new mail window).
3. Click Mail, then Editor Options
4. Select Advanced and look near the bottom of the dialog for the option to Show Picture Placeholders.
5. Close Outlook and re-open.




You can also try the following:

1. In main outlook window > File > Options > Trust Center
2. In the right pane click on Trust Center Settings
3. In the new window opens, click on Automatic Download from the left menu.
4. Un-check the “Do not download pictures automatically”
5. Close and re-open outlook

I hope this helps.

Power Tactics


What power tactics do people use to translate power bases into specific action?   What options do they have for influencing their bosses, co-workers, or employees?     Research has identified nine distinct influence tactics:

  • Legitimacy.  Relying on your authority position or saying a request accords with organizational policies or rules.
  • Rational persuasion.  Presenting logical arguments and factual evidence to demonstrate a request is reasonable.
  • Inspirational appeals.  Developing emotional commitment by appealing to target’s values, needs, hopes, and aspirations.
  • Consultation.  Increasing the target’s support by involving him or her in deciding how you will accomplish your plan.
  • Exchange.  Rewarding the target with benefits or favors in exchange for following a request.
  • Personal appeals.  Asking for compliance based on friendship or loyalty.
  • Ingratiation.  Using flattery, praise, or friendly behavior prior to making a request.
  • Pressure.  Using warnings, repeated demands, and threats.
  • Coalitions.  Enlisting the aid or support of others to persuade the target to agree.

Pressure is typically tends to backfire and is typically the least effective of nine tactics. You can also increase your chance of success by using more than one type of tactic at the same time or sequentially, as long as your choices are compatible.

Quoted from the book ” Organizational Behavior  –  Stephen P. Robbins   .   Timothy A. Judge “

How to Remove a Blank Page in Word

Many Times when I create a report with MS Word I get that annoying Extra Blank page at the end of the document,  and it annoying especially when you convert a document to a PDF file and send it to someone.    I tried every thing and still ouldn’t delete that extra blank page till I found that vedio which explains how easily you can remove that page:

Array Address not changed after changing IP address of Forefront TMG 2010

Recently we have changed the IP address of our Forefront TMG 2010 Standard server.    Then after a while the Event viewer began to record errors related to the Array address,  the Event was as follows:

14158 : The IP address specified for communication between this Forefront TMG computer (old ip address) and other array members is not bound to a network adapter installed on this computer. The IP address specified for intra-array communication must be bound to a network adapter installed on the computer.

I have reviewed the configuration of the Network cards and found nothing related to the old address, but by futher investigation, I found the following configuration which needs to be canged:

1) Open:    Forefront TMG Management console -> Firewall Policy -> Network Objects -> Computer Sets -> Array Servers.

Found the old IP address still there,  then changed to the new address.

2) Open and change the old ip address in the following two locations:

– SQL Server Configuration Manager -> SQL Server Network Configuration -> Protocols for MSFW-> TCP/IP -> IP Addresses tab

– SQL Server Configuration Manager -> SQL Server Network Configuration -> Protocols for ISARS -> TCP/IP -> IP Addresses tab

3) Open the registry editor for ” msFPCIntraArrayAddress ” and chnage the the old IP address for the entries found (four entries)

4) Search the registry for all entries with the old IP address and chnage it to the the new address

5) Restart the TMG Server

ActiveSync is not working on Android – for some users

When you have everything is correctly setup and your users can use ActiveSync on their Android phones, and at the same time there are some users may not be able to use it on Android, and when they setup their accounts on their phones, they have an error message “Failed to create the account. Please try again later”

After searching the internet and some forums, I found the solution:

1- Go to Active Directory users and computers

2- From the menu:  select View > Advanced Features

3- Select the user who has this problem

4- In his account properties, select the Security tab

5- Click Advanced button

6- In the Permissions tab check the box at the bottom for “Include inheritable permissions from this object’s parent”

7- You may need to wait 5-10 minutes for Active Directory to propagate the changes if have a large environment.

8- Now try to setup the account on the Android phone again.