Table of Contents [ClusterReplica SQL v2.1 User Manual]

Transcription

1 i Table of Contents [ClusterReplica SQL v2.1 User Manual] CHAPTER Introduction What is ClusterReplica MSSQL Edition Who is ClusterReplica MSSQL Edition Designed For How Does ClusterReplica MSSQL Edition Work How to get help...4 CHAPTER Installing/Removing ClusterReplica MSSQL Edition System Requirements Installation Guide Running the evaluation package Removing ClusterReplica...14 CHAPTER Understand ClusterReplica MSSQL Edition Status Checking the Status on Your Cluster Server Cluster Configuration Alert...20 CHAPTER Data Replication Auto-config For MSSQL Database File Data Replication Data Replication Tools...23 CHAPTER Failover Solutions When to Use Application Failover Two Levels of Failover How To Failback...30 CHAPTER Utility Tools Network Application Scanner Network Utilities Port Reference Table...33

2 1 Chapter 1 Introduction 1.1 What is ClusterReplica MSSQL Edition ClusterReplica MSSQL edition is a computer software that features data replication and failover/failback solutions. In addition to all its standard features, this edition specialize in handling MSSQL database file replications. Running on two Microsoft windows systems, ClusterReplica bind them together and backup data from the ACTIVE station to the STANDBY station when both systems are alive. In the situation of failure of the ACTIVE station, failover will take place automatically. When this happens, the STANDBY station will then take up the ACTIVE role to continue server service. There are also added features of Network Application Scanner, Port Reference table and other network utilities. The combined product of ClusterReplica is, therefore, a powerful network server application of all purposes. 1.2 Who is ClusterReplica MSSQL Edition Designed For ClusterReplica MSSQL is fully functional data replication software specially designed for small business owners. With automatic default configuration on MSSQL database file replication, small business owners can utilize the software without having to hire IT experts to setup the cluster server to run ClusterReplica MSSQL edition. Running on Microsoft s windows systems, the comprehensive user interface with buttons to open up the configuration dialog boxes also made the software very easy to use. The detailed online help and the talk to the person kind of technical support ensure the success run of the software. Besides the easy to use advantage, ClusterReplica MSSQL edition is also reasonably priced. With the inclusion of many network utilities, ClusterReplica MSSQL edition software brings true value to small businesses.

3 2 1.3 How Does ClusterReplica MSSQL Edition Work ClusterReplica MSSQL binds two Microsoft Windows systems together to function as one server, so that there will be at least one system running normally to server the network clients requests. Of the two systems clustered together, one is taking the ACTIVE role to be the Primary station, and the other taking the STANDBY role to be the Secondary station. During standard condition, both systems are running normally, the Primary station will service the network clients directly and replicate all newly changed data to the Secondary station to keep it current with all data. This continuous data replication works on open and locked files including the database files. The process ensures all changed data updated at all time. No data will be lost due to system failure or the service down, and server service should be available 24/7. Between the two clustered stations, the communication is conveyed by the Control IP which is the IP number defined on the network card. There is also a Cluster IP which is a virtual IP attached to the Control IP number of the Primary station. For example, you have one network card on each of the clustered systems. Your public IP for network connection is You then define the IP numbers of the network cards and When you install ClusterReplica, you choose the system with IP to be the Primary system, and set to be the Cluster IP. This Cluster IP will be attached to the Control IP of

4 3 With this setting, the Control IP and the Cluster IP are in the same sub-net. This means both internal and external communications are sharing the same network channel. If there is large volume of client service requests, the service performance may be reduced. It is for this reason, two network cards for each of the clustered systems are commended. With two cards, you can designate one to take care of the internal communications only, and the other for the public connections. For example, you have two network cards on each of the clustered systems. Your public IP for network connection is still You then set the IP numbers of the network cards and on one system, and Set and on the other system Because is your public IP, when you install ClusterReplica, You will use the 195 set of IPs for the internal communication between the clustered systems You set the system with IP to be the Primary system, And set to be the Cluster IP. This Cluster IP will be attached to the Control IP of With this setting, the network traffic flow will not interfere with the clustered systems internal communication, and therefore, improves server performance.

5 4 1.4 How to get help Due to complex system configurations of ClusterReplica MSSQL Edition, XLink specially designed an "Error Report" log file. Users must follow listed steps to generate this report log. From ClusterReplica user interface, click Help on the menu bar, then select Generate Report for Support, following dialog box will come up. Fill in the information with description of your problem, then click "Next". Next screen confirms the input. If you wish to make changes, click "Back" to go back to previous page. If all looks right, click "finish" to begin building the log file.

6 5 Now you have generated the error log. Go to C:\XLinkCRReport to find the file "Reportsetup.txt". this file to and we will contact you for possible solutions. If you have quick questions regarding this product, please feel free to contact us. Phone: fax:

7 6 Chapter 2 Installing/Removing ClusterReplica MSSQL Edition A cluster server requires internal communication between the clustered systems as well as external communication with the network clients. ClusterReplica MSSQL edition introduces the concept of "Control IP" and "Cluster IP" to distinguish the two functions. While the "Control IP" handles the internal communication between the clustered servers using the IP numbers physically attached to a network card on each machine, "Cluster IP" deals with public connection requests running on a Windows virtual IP that is attached to the control IP of the Primary Station. 2.1 System Requirements Two Microsoft Windows systems of 2000/XP/2003 platforms with Ethernet connection RAM: 128MB or above Hard disk: 8GB or larger Network connections between the clustered systems Both systems must be in the same subnet 2.11 One network card or two If the systems you are going to install ClusterReplica MSSQL edition each has one network card, this means the clustered systems operate under one network environment - both internal and external communications are moving within one network. Therefore, the server performance is heavily dependent on the capacity of the network card. This environment can be risky to the clustered server normal function, and at the same time limiting its performance. If the systems you are going to install ClusterReplica MSSQL edition each has two network cards on each system, you can designate one set of IPs as the "Control IP" and the other set "Cluster IP". This separation allows you to define a different subnet for the "Control IP" so that the internal communication will not tangle up with the service provide IP for public connections. This setting will certainly enhance your server performance and guarantee accurate data replication.

8 7 First, let's look at the situation of one network card Your public IP for network connection is You then define the IP numbers of the network cards and When you install ClusterReplica, you choose the system with IP to be the Primary system, and set to be the Cluster IP. This Cluster IP will be attached to the Control IP of When the Primary station is down, Failover will take place. The Secondary station takes up the ACTIVE role now to become the Primary station. The Cluster IP: is now attached to the Control IP of

9 8 When the failed system is fixed and connected back to the cluster system, it will take up the STANDBY role to become the Secondary station while the Primary station remains its ACTIVE role. With this setting, the Control IP and the Cluster IP are in the same sub-net. This means both internal and external communications are sharing the same network channel. If there is large volume of client service requests, the service performance may be reduced. It is for this reason, two network cards for each of the clustered systems are recommended. With two cards, you can designate one to take care of the internal communications only, and the other for the public connections. Now, we look at the situation of two network cards Your public IP for network connection is still You then set the IP numbers of the network cards and on one system, and Set and on the other system Because is your public IP, when you install ClusterReplica, you will use the 195 set of IPs for the internal communication between the clustered systems. You set the system with IP to be the Primary system, And set to be the Cluster IP. This Cluster IP will be attached to the Control IP of

10 9 With this setting, the network traffic flow will not interfere with the clustered systems internal communication, and therefore, improves server performance. Also the separation of internal and external communication could help to increase file security. 2.2 Installation Guide Before install, please check the system requirements to make sure your system can handle the software properly. Some other guiding points are listed blow: One license key is to be used on both systems for installation. If each of the servers has two network cards, be sure that at least one additional IP of the same subnet for each card is added before installation. The Primary station must be installed and running before the Secondary station is installed. Upon completion of installation and system reboot of the Secondary station, a pop-up reminder will come up to ensure this point.

11 10 With a successful download, you will get the ClusterReplica_sql.exe file as the installer. Double click on it to start installation process. The first screen as seen below greets you with the product name and version number. Click on button Next to move on. Following message box will come up to remind you the software requires a member of administrator group to perform the installation. If you are already logged in as a member of the administrators, click on yes to continue. Along the way, you will see the license agreement with conditions on using the software properly.

12 11 Read the agreement carefully and be sure you fully understand every term listed and that you agree with this agreement entirely before proceed with the installation. Click No if you disagree with any of the terms listed in the license agreement. The installation process will be stopped. If you clicked "Yes" in 3, the next screen prompts you to fill in your name, the company s name and the product s serial number which is the license key you have purchased for using the product. The serial number box is filled with DEMO as the default entry. If you have not purchase a license for the product and just want to install the demo package, leave this default entry in the box and click on next to continue. The next screen asks you to decide if you want to set the local system as the Primary system or the Secondary system. Select one and continue.

13 12 Make your selection and click Next (this example uses the Primary station installation). This next screen will come up for you to set the Cluster information. You will type in the "Cluster name" (call it anything you want), select a network card that is to be dedicated for public connection and Browse/select or type in the IP number and the IP mask. Two situations to be considered: 1. You want to use only one network card in each of the clustered systems: in this situation, both internal and external communication will be accessing the same subnet. 2. You want to dedicate two network cards in each of the clustered systems: in this situation, you can use one card for Control IP and another card for Cluster IP. We recommend to use two network cards for the clustering: one is dedicated to the internal communication, one is dedicated to the public connection. This setting works for better security and efficiency in the cluster server. The next pop-up screen will come up for you to select the matching network card. The "Property" button is there to help you find out which number is attached to which card if you have more than one card in the system.

14 13 Click "OK" to move on. If you didn't already setup the additional IP number for the network card, you will see the pop-up error message. Now, you will have to abort the installation process. Go to Windows network configuration and add the IP number to the card and try to install ClusterReplica again. If you don't see the error message, installation process will move on. With a few more clicks to bring you to the last screen. Now you have successfully installed ClusterReplica MSSQL edition software. It is recommended to reboot the system immediately after the installation so that the software is fully recognized by the operating system and the system resources can be fully utilized. Otherwise unpredictable problems can rise.

15 Running the evaluation package ClusterReplica MSSQL Edition, like all other Xlink s products, has a 30-day evaluation period. This means you can download a copy of ClusterReplicaMSSQL Edition from our web site and test run it for 15 days to decide if the software fits your needs and system environment. We encourage and recommend you to take advantage of the evaluation package and make sure you can use the software before purchase. 1.4 Removing ClusterReplica ClusterReplica MSSQL Edition is equipped with its own uninstall program. You can find it by clicking on Windows Start/Programs/Xlink ClusterReplica. If for any reason you want to remove the software from your system, run this uninstall program will remove all files of it. Using Windows add/remove program should reach the same result. Be sure to reboot the system after running uninstall.

16 15 Chapter 3 Understand ClusterReplica MSSQL Edition Status With successful installation of both Primary and Secondary stations, ClusterReplica MSSQL edition will automatically establish the clustering between the systems. Its main user interface is the status screen for users checking on the cluster server running state. To view server status, from Windows "Start" menu, select Programs\Xlink ClusterReplica MSSQL edition\clusterreplica MSSQL edition Configuration 3.1 Checking the Status on Your Cluster Server Following is the status screen on the Primary station which both clustered systems are running normally without any data replication activities. When there is data replication activity taking place between the clustered systems, the progress of this activity will be displayed in the Replication Status Window. This data replication progress status display is the same on both clustered systems.

17 16 The main points on this screen are explained below: Cluster Role - It indicates the current role of function of the local system, which can be either the Primary or Secondary system. ClusterReplica MSSQL edition is designed in the way that after their initial setting of being Primary and Secondary station, the one that started first will take the role of being the Primary station. Local System - On both clustered systems, the "local System" is listed on the top. So, do not be confused here: if you are looking at a Primary Station, you see one set of specifications; and then looking at a Secondary Station, you will see a different set of specifications under "Local System". This is because the "local system" is different now. Control IP - This pair of IP addresses are the ones responsible for the communication between the clustered systems. They are not to be seen by the network clients. Start Time - Please notice that the Start Time for the "local system" and "remote system" is a little different: the Primary Station is always started before the Secondary Station. The implication of this difference in timing is that the system that starts first will be the "Primary Station. Cluster Status - For each of the clustered system, there are three roles it can take: 1. The ACTIVE role of being the Primary Station 2. The STANDBY role of being the Secondary Station 3. To be the Primary Station running in "Stand alone" mode When the Primary Station fails to function normally, either one of the data related service failed or the entire system is down, the ACTIVE role of the clustered server will be failed over to the Secondary Station which will now be running in "stand alone" mode. Its status screen will look like the picture below.

18 17 The three buttons on this status screen are: 1. Refresh - click this button to capture the latest cluster status 2. View Cluster Log - click this button to view the history of cluster role status of the local station 3. Switch Role - click this button to switch the role of ACTIVE/STANDBY of the clustered stations. Confirmation of this action will display to avoid loss of data. A Cluster Log is provided to help users track the cluster server's status. As shown in picture below, though showing only the status of the Primary (Active) server, the overall cluster server s status is implied. The needs for role switching normally comes up after a system failover. When the original Primary Station (the one that has the box preferred primary station checked in the Cluster configuration panel) is fixed and up again, you will be asked to decide either to keep the current Primary station as is, or switch the ACTIVE role back to the original Primary station. NOTE: it is strongly recommended that the newly turned-on station of a cluster system to be kept as the Secondary station until all new data are copied to it.

19 Cluster Configuration During operation of ClusterReplica, if for any reason you need to change the current settings of the clustered systems, select Cluster Configuration from the main menu of this screen. Things can be changed here: Change the communication port - The default port used for communication between the clustered systems is User can change it to a different port if needed. Switch role of preferred primary station - This preferred primary station is a pre-set condition and does not change with the current role of the system. So, the system can be either the Primary or the Secondary station while being the preferred primary station. For example: When you install ClusterReplica, you set system A to be the preferred primary station. System A becomes the Primary station when installation of ClusterReplia completes. Then during the course of operation, system A, the Primary station, is down and Failover takes place. System B, the Secondary station is now the Primary station working in STAND ALONE mode.

20 19 When system A is plugged back to the cluster system, it may be set as the Secondary station, even though it is still carrying the status of preferred primary station. Change Control IP - This is the IP that responsible for the internal communication of the clustered systems. These are the IP addresses attached to the network cards on the Primary and the Secondary stations. They are not known to the network clients. When changing these IPs, you must select the matching network cards to ensure proper operation of the cluster system. Change ClusterIP - This is the IP that the network clients use to make connection to the clustered server. More than one cluster IP addresses can be assigned for public use. To change it, you remove the current one and add the new one. Change the name for the Cluster system - This is the name for the cluster system to be recognized by the network clients. You can call it anything you want. Change the advanced setting for failover - Three kinds of configurations can be changed here: 1. Failover timer - The first setting controls the time duration in which a failover decision would be made. In normal condition, the Secondary station monitors the activity of the Primary station continuously. If an abnormal condition is detected and it lasts 20 seconds, the Secondary station will activate failover to become the Primary station. Users can adjust this time duration of monitoring. However, if made too short and the clustered systems are not given enough time to respond and process, the cluster system could get confused and causing problems. 2. Modified services fail to start - The second setting involves service level failover. It is set by default for high standard failover.

21 20 3. Public cluster NIC fail to function - The next setting is available for detecting failure of the network card on the Primary station. When it is set, failover will take place when the network card failure is detected Alert In two situations this feature can show importance: 1. When a Failover occurs 2. When a Data Replication definition item is disabled by ClusterReplica process to prevent improper data replication With proper setup of this tool, system administrators will be notified of happening of above situation. To set it up, from ClusterReplica s main status window, click the tool bar button Options, then select alert setup. This is an example to show you how alert can be set.

22 21 Chapter 4 Data Replication ClusterReplica's data replication is among the most powerful and efficient in its class. Besides handling all types of files, including SQL database files and some registry files, ClusterReplica replicates modified data in real time even when the file is open and being used. With successful installation, this edition of ClusterReplica will automatically configure the software to replicate MSSQL database files and activate Failover when the MSSQL service or the entire system failure is detected. 4.1 Auto-config For MSSQL Database File Data Replication Select Replication Setup for MSSQL" from the main menu, the GUI panel will look like following picture. Data replication configuration is defined in the right-hand-side penal. This penal is divided into three parts with some tool buttons on the top for user interaction. Details of these are explained below.

23 22 Buttons on the tool bar Option - To set file replication verification schedule Sync - To perform file replication manually Log - To check the file replication status Refresh - Re-load the existing configuration (any change you made without saving will be lost with click of this button) Config - To change file replication configurations Default - To re-load the default file replication configuration set Notice there are three parts to be configured: 1. Data Replication Setup - Add all files and folders of files to be replicated from the Primary station to the Secondary station here. If a file requires an application to access, the application/service must be added in the Monitored Service section. 2. Registry Replication - The Registry Replication functionality meets the needs of some server systems which require certain dynamically changed key definitions of registry matched on the Secondary server for a successful failover. Warning: Do not replicate the entire registry - replicate only the keys for specific applications. 3. Monitored Service - All files that need specific application to access (for example, the database files require SLQ application to access), would require to have the application service to be added in this section for successful Failover. Please also notice that there are already "stuff" in each of the sections in this GUI panel. This is because the special edition of ClusterReplica MSSQL has configure the software to replicate MSSQL database files for you. The "stuff" in each section of this panel are the files and services needed for ClusterReplica to correctly replicate all your MSSQL database files from the Primary station to the Secondary station at normal times, and activate Failover process when a service or system failure is detected. If there are other application files need to be replicated, click the button Config to open up the dialog box for making changes. Click Add to add files and services you want to replicate and failover. In above example, the C:\inetput\wwwroot file path is added for the web site pages. Services IISADMIN, WWW and the simple mail service are added. These additions will support data replication on files in the wwwroot folder and failover when web service is detected failing.

24 Data Replication Tools The menu bar of data replication configuration setting panel provides some additional tools are included to help users better manage data replication and ensure data replication accuracy Data Replication Log Click on log button to open up following window that lists the events of data replication.

25 24 From this log, you can trace the replication actions on files or folders and then decide if some files or folders are not properly replicated that you need to do it again Data Replication Tools Click button Tools you will get two selections: Compare File Info and Options which in turn includes two selections: Verification Schedule and Advanced Settings. 1) Compare File Info The "Compare Replication File Info" tool allows you to manually check up the folders and files in the File Replication definitions to make sure all files are copied properly from the Primary server to the Secondary server. When in File Replication Setup, click button Advanced on the menu bar to find Compare File Info to open up the processing screen as shown below. The first thing to setup here is how you want the comparison result to display. Click the button Filter on the menu bar to get next dialog box. Select the display option according to your needs and click OK. The default setting is on Display all results.

26 25 The next thing to do is to find the source file of the replication. Browse by click button to select the folder of a File Replication definition. Click button to get the comparison results. By default, all files and folders are to be listed. If there are problems in some replicated files, you may find wordings such as file does not exist in the Remark column. 2) Replication Verification Schedule ClusterReplica can run automatic data replication verifications which will auto update files on the Secondary system whose file dates or file size does not match that on the Primary system. The default set on this data replication verification is as shown. You can change the verification schedule according to your needs.

27 26 3) Advanced Settings ClusterReplica replicates modified data of database files and regular files in the point-in-time fashion. The system is pre-set with memory space allocation and time-out values considered to be most efficient to the cluster system. Users, however, are still given the power to change these values to the best they consider best fit to their needs. This flexibility promises the highest user satisfaction.

28 27 Chapter 5 Failover Solutions ClusterReplica provide Failover function to allow the cluster server maintain all its services in correct working state. 5.1 When to Use Application Failover Failover is the process specifically associated to cluster systems. Typically it means when the Primary station of a cluster system dies, the Secondary station will be activated to take over the active duty of the Primary station. XLink's ClusterReplica software will monitor the systems in the cluster system and the pre-defined services to determine if the cluster system is in the situation that a failover is required. So, all applications and services you want to keep up 24/7 should be defined here. 5.2 Two Levels of Failover ClusterReplica determines activation of failover on three types of conditions: 1. System failover - This happens when the entire Primary system is down 2. Service level failover - When any one of the monitored services is not functioning normally 3. The network card failure - When the network card on the Primary station for public connection fails, failover will take place System Level Failover The first picture (1) below shows a normal working situation of the cluster server. When the Primary station fails, the Secondary Station will become the Primary station and work in STAND ALONE mode as seen in picture (2).

29 28 If you have set the original Primary station, the failed station here, as the preferred primary station, when it is plugged back in the cluster system again, you will be asked if you still want to run it as the Primary station. This is because by design, the data flow of the cluster system is always from Primary to Secondary system. This means, if you choose to set the newly turned-on system as the Primary system, all data on the current STAND ALONE system will be lost. Therefore, it is important that you first copy all updated files back to the newly turned-on system before you make it to be the Primary station. You would not see this pop-up question if the STAND ALONE system is already the preferred primary station. So, leaving the system marked as the preferred primary station as the Secondary system so that all current data on the STAND ALONE system will be copied to it, picture (3). When this "data copy back" process is completed and both systems are having the current data, then you can switch roles of the systems if you really want to, picture (4).

30 29 Service Level Failover Failover will take place when one of the services fails to function normally. In this situation, both clustered systems will be running. However, their roles of ACTIVE and STANDBY will be switched automatically. Please note, cluster system reset is required after each occurrence of service level Failover. For example: You set MSSQL server service for failover. One day, it somehow stopped working on the Primary Station. Then failover takes place - the Secondary Station is now taking over the ACTIVE role and becoming the Primary Station. (as in picture (1) and picture (3)) However, data replication for the SQL database, in this setting, will not work. So, fix up the SQL server should be your first priority. Now, if you fixed the SQL service on the Secondary system (as in picture (3)) without having to reboot it, you need to reset the cluster system to enable the service level Failover function. There are three ways to reset this condition (as in picture (3)) 1. Reboot the STANDBY station. 2. Manually switch the roles of ACTIVE and STANDBY system. 3. Reboot the Primary Station - this will cause a system level Failover to occur and resulting switch of the roles of the systems. NOTE: when the ACTIVE station is changed to become the STANDBY Station, you know there is a service or application on that system failed to function normally. You should exam the Secondary station and fix the problem without delay. Resetting the cluster system is also important. When the network card on the Primary station used for public connection failed, failover could also take place. The Secondary station will be activated and network clients would be able to connect to the server through its network card.

31 How To Failback Failback is the process to switch the role of Primary station from the current ACTIVE system to the current STANDBY system or a newly turned-on system. To understand ClusterReplica's Failback process, two concepts related to a cluster system need to be clarified: Preferred Primary Station - This setting servers as a marker to remind you that the system is originally intended as the Primary station. It can be re-configured in the Cluster Configuration section. Data flow direction - Data flow in a cluster system is normally from the Primary station to the Secondary station. When trying to Failback, the main issue that would concern you is to keep server function with all current data available. A successful Failback requires having all current data copied onto the newly switched on system from the current Primary station. When dealing with Failback, two situations are to be consider: 1. The newly turned-on system was originally set as the preferred primary station 2. The newly turned-on system was NOT originally set as the preferred primary station In the first situation, when the new system is plugged back in the cluster system, you will be asked if you still want to run it as the Primary station. Keep in mind that the data flow of the cluster system is always from Primary to Secondary system. This means, if you choose to set the newly turned-on system as the Primary station, all data on the current Primary station will be lost. Therefore, it is important that when you first connect the new system into the cluster system, set it as the Secondary station so that you updated files can be copied to it before you switch it to become the Primary station. In the second situation, no question will be asked. This is so because it is assumed that the newly turned-on system was initially intended to be used as the Secondary station. It will stay to be the Secondary station when re-join the cluster system.

32 31 Chapter 6 Utility Tools For users convenience, ClusterReplica also includes some utility tools. From ClusterReplica program list, select the utilities that can be helpful to manage your server applications. 6.1 Network Application Scanner The Network Application Scanner can scan the operating system and find out all network applications running on it. From its dialog box, click on button scan to get the services of all applications currently running on the system listed. Click on button Details will get a popup box to come up showing you the detailed information of the network application.

33 Network Utilities There are times when a user needs to know the IP address of a registered host, or the network transaction routing path. ClusterReplica s Network Utilities tool can help you achieving this objective. This network utility tool consists of two features: Host Lookup and Trace Rout. Host Lookup Host Lookup can help users match the IP address of a web host with its name. As shown in figure 6.1 below, to find the IP address of yahoo, type yahoo.com in the host name window and click on button Look Up. The IP address for yahoo.com will be found and filled in the IP Address window. A reverse lookup can also be done using Host Lookup. In this case, user simply types in the IP address to find the registered host s name. Trace Route The second feature in Network Utilities is Trace Route. This tool is created to help users trace the routing path of service providers between the host and the traced servers. Up to 20 router activities will be listed. It is fairly simple to use this tool. Select Trace Route tab from the Network Utilities GUI, type in the Host s IP address and then click on button Trace. The packet routing path of all internet service providers (up to 20) will be listed in the Trace status screen.

34 Port Reference Table The Port Reference Table lists some of the most commonly used ports with description as reference for users. On the menu, Default will bring up the default listing. Modify allows changing of a port s description. New port definition can be created in New. Click on the column title Port Number will sort the port numbers in ascending order; and Description will sort the port descriptions in ascending alphabetical order.