Paessler Blog
Archive for "2007"
2007-Nov-14
Downtime of paessler.com website due to a traffic accident
Apparently a traffic accident is to blame for almost 3 hours of downtime for our corporate websites in the night from Monday to Tuesday. A truck driver lost control over his vehicle due to low blood sugar and drove into a power transformer on the side of the Dallas-area data center of Rackspace Inc. in Grapevine, Texas, which hosts our server park.2007-Oct-19
Handy SNMP resources on the Cisco website: Cisco MIB Listings, MIB Locator, and OID Translator
Recently we came across the following three pretty notable pages provided by Cisco, allowing users to find Cisco MIBs and to discern OID segment almost at a glance.2007-Oct-17
Bug in Cisco ASA 5505 causes PRTG to report the same traffic on all VLANs
We have had multiple queries regarding strange, respectively wrong readouts when monitoring certain ASA equipment. As we found out today, the problem is a bug in the 7.2 OS causing the SNMP iftable to forward erroneous return values to monitoring software, such as PRTG. Instead of graphing PER vlan values, this bug results in graphing the total number of untagged vlan packets for each vlan.2007-Oct- 8
WindowsIT Pro mentions PRTG in the "8 More Absolutely Cool, Totally Free Utilities" list
2007-Sep-12
Most common causes of network outage include inadequate bandwidth, excessive file streaming and device misconfiguration
Our latest press release reports about the latest survey results from users of PRTG Traffic Grapher. It reveals that bandwidth management software is a key component in preventing network downtime.2007-Aug-29
Negative PING times on AMD Dual Core Processors - Solved
[UPDATE Oct 2010] There seems to be an easier solution than the one mentioned below: By using the "/usepmtimer" boot.ini flag (simply add this line to boot.ini) you can change the time source for QueryPerformanceCounter from TSC to the PM timer which is a global time source. Note: This information was taken from here and http://wiki.ljackson.us/Negative_Ping_Time#BOOT.ini_Solution, but we did not test it ourselves on AMD CPUs). -------------- In recent weeks we have received reports about negative PING time measurements (e.g. -5 ms) from users of our monitoring products. "Great", we thought, "our software has overcome the laws the physics and is able to received network packets before they are actually sent". But now there are more and more hints showing up around the Internet that we will not receive the Nobel price in physics...2007-Aug-20
New Version 5.4.1 of IPCheck Server Monitor adds WMI Sensors and Vista Support
Today we have released the latest version 5.4.1 of IPCheck Server Monitor. The main new feature is support for five new sensors based on WMI2007-Jul-17
Survey Finds PRTG Traffic Grapher Saves Network Administrators Hours a Week in Network Monitoring Time
2007-Jul-10
Latest IPCheck beta version adds WMI sensors and support for Vista
The latest beta for IPCheck Server Monitor version 5.4.1 mainly adds two new features: WMI sensors and Vista support.2007-Jul- 9
Detecting Common Network Problems, Part VII: Intrusions
Intrusions to your network can easily occur at anytime and often come from unexpected sources. Intrusions from hackers, internet worms, viruses, Trojans, or just people curious about what you happen to have on your network pose great threat to the security of you network. Network Monitoring allows you to identify network weaknesses, as well as detect intrusions should they occur.2007-Jul- 6
How to set up audible notifications for PRTG and IPCheck using speech synthesis software
2007-Jul- 5
SNMP on Windows Vista rendered dysfunctional by NOD32 Anti Virus
Since Vista came out we had a strange problem with our Vista workstations: We were absolutely not able to query them through SNMP (using our PRTG or IPCheck as well as any other SNMP tool). SNMP requests simply timed out and were not returned by these Vista machine, regardless of the version (Vista Business or Ultimate). The SNMP service was properly installed and working, netstat reported nothing unusual.2007-Jul- 5
Detecting Common Network Problems, Part VI: Software Problems
Software-related network problems can cause one or more computers or devices to lose the ability to communicate with other devices on or outside the network.2007-Jul- 4
GameData, Inc. keeps Counter-Strike community website up and running with Paessler PRTG and IPCheck
2007-Jul- 2
Detecting Common Network Problems, Part V: Network Collisions
Although the word sounds negative, collisions are a normal part of a healthy network. A collision is the mechanism used by the network to control access and to allocate shared bandwidth among devices that want to transmit at the same time on a shared medium. Collision detection allows the two devices to identify that they both want to transmit at the same time. While collisions are normal, a high collision rate can indicate network problems.2007-Jun-28
Detecting Common Network Problems, Part IV: Connectivity Problems
Connectivity problems occur when devices on the network cannot communicate with other areas of the network due to hardware or software problems. With Network Monitoring, you can detect a connectivity problem before users or customers even notice it.2007-Jun-25
Detecting Common Network Problems, Part III: Hardware Problems
Hardware problems occur when a network device is not working properly and cannot send or receive some or all data. With the myriad of hardware devices connected to the network at any given time (including routers, firewalls, servers, switches, etc.), detecting when a specific device malfunctions is vital.2007-Jun-21
Detecting Common Network Problems, Part II: Cable Problems
Cables are a vital part of any network. Cables are also prone to wear and tear, which can cause problems across the network. The obvious solution would be to make sure you install cables in places that do not get a lot of foot traffic, or places hidden from curious hands. The fact is, somewhere on the network, there are probably at least a few cables exposed to possible damage.2007-Jun-18
Detecting Common Network Problems
Network Monitoring allows you to accurately recognize and diagnose networking problems with the goal of keeping your network running optimally. Your network is a vital business asset, and maintaining maximum uptime and availability is the highest priority. To keep your business operations and processes running smoothly, 24x7x365 monitoring and notification are required to detect the various problems, failures, and performance issues before they have a chance to affect your employees or customers.2007-Jun-13
Web 2.0 & Co. Demand a Robust Performance
For all e-enterprises a well designed and reliable web page has to be part and parcel of the marketing mix - especially as the online presence often establishes that vitally important, initial customer contact. A wrongly conceived web server and overburdened pages that take too long to load and respond, are both frustrating and an unnecessary obstacle for customers and provider.2007-Jun- 4
Preparing for the Moment of Disaster
Monitoring, knowing what to monitor, and knowing whom to tell, still do not provide the whole solution for proper Network Monitoring; you must also know what to do when monitoring discovers problems.2007-Jun- 1
What does the sensor name "Error converting OID" mean when creating sensors using an OIDLIB in PRTG
After converting a vendor specific MIB file into a Paessler oidlib with Paessler's MIB Importer Tool and using this oidlib as source for the creation of a SNMP sensor in PRTG, "Error converting OID" appears in the name of the sensor. The sensor, however, works as expected.2007-May-31
OK, you are monitoring your network. Now: Whom To Tell The Results
Once you perform regular monitoring, it will not help if you keep all the results and findings to yourself. Knowing whom to tell what information, and when to tell it, is a major necessity.2007-May-29
The three most important readings that you should monitor
Merely implementing a Network Monitoring solution is not enough. You should also know which aspects of your network need monitoring.2007-May- 3
Creating websites for high traffic
When creating websites for high traffic the magic keyword is "scaling". There is an interesting presentation by Cal Henderson (architect with flickr.com) available on slideshare.com which covers this topic.2007-Feb-27
Windows Event ID 7039 on machines running PRTG Traffic Grapher
If you run PRTG Traffic Grapher as a service on your computer you may see Windows Event ID 7039 in your System Event log.2007-Feb-19
Changes in the Daylight Saving Time in the USA and their impact on IPCheck and PRTG
The U.S. Energy Policy Act of 2005 extended Daylight Saving Time (DST) in the U.S. by approximately four weeks. As a result, beginning in 2007, DST will start three weeks earlier on March 11, 2007, and end one week later on November 4, 2007, resulting in a new DST period that is four weeks longer than previously observed. If your computer runs on an American or Canadian Timezone setting this situation affects your computer and software.2007-Feb- 1
Fiddler HTTP Debugging Proxy
Fiddler (by Microsoft) is an interesting HTTP Debugging Proxy which logs all HTTP traffic between your computer and the Internet. Fiddler allows you to inspect all HTTP Traffic, set breakpoints, and "fiddle" with incoming or outgoing data.2007-Jan-31
Increasing the width of the taglist in PRTG's web interface
Some users have asked us how they can increase the width of the taglist in PRTG's web interface. They use longer tag names and/or group names which are cropped when they use PRTG's default setting for the width of the left column. Changing the width is actually pretty easy: One must only edit the widths in the CSS file.2007-Jan-30
Load testing web applications that use Flash animations
Today we have received this typical question: "I'm trying to find a load testing product which would allow me to load test flash applications. I've tried webserver stress tool 7 and it doesn't seem to enable me to simulate usage of a flash application. Can you tell me if this can be done, and if so, how? " The answer is a straight well..... yes.2007-Jan-24
Setting up SQL Server Sensors for MS-SQL, MySQL and Oracle with IPCheck Server Monitor
Using the SQL Server sensors you can natively monitor the most used SQL servers: MySQL, Microsoft SQL, and Oracle SQL. Basically, the sensors monitor whether the database server process- A: accepts connections and
- B: processes requests and
- C: returns an expected result when executing a custom SQL command.
2007-Jan- 9
Details about the meaning of the "Busy Sensors" value in PRTG Traffic Grapher
While you are using the Windows GUI of PRTG you will see a "Busy Sensors" value in the statusbar. In larger installations or installations with small intervalls you should have an eye on this value because it can tell you wether your PRTG setup may be close to an overload.2007-Jan- 8
"This program has been damaged..." messages when starting Paessler programs
If you receive the message "This program has been damaged, possibly by a bad sector of the hard drive or a virus. Please reinstall it." when starting IPCheck Server Monitor, PRTG Traffic Grapher or Webserver Stress Tool then you either have a virus or trojan on your computer or a malfunctioning anti-spyware software.2007-Jan- 7