Using ZENworks for Servers 3 SMNP Agents to Manage ServersZENworks for Servers 3 has several management agents that enable you to configure, monitor, and manage servers from a single console interface. Understanding SNMP-Based Server ManagementOne of the biggest advantages in using ZENworks for Servers 3 to manage your servers is that its server management agents support the industry standard Simple Network Management Protocol (SNMP). These ZENworks for Servers 3 server management agents also support the UDP/IP, IPX, and NCP implementations for packet sending. Therefore, any SNMP console or manager can request information from them. The ZENworks for Servers 3 server management agents run on both NetWare and Windows NT/2000 Servers in your network. These agents continuously monitor the servers and collect dynamic data in response to requests from the management console. ZENworks for Servers 3 uses several different management agents to manage servers.
NOTE The ZENworks for Servers 3 SNMP agents must be installed on every server you want to manage. Discussing the ZENworks for Servers 3 Management ViewsThe ZENworks for Servers 3 management agents provide information to the administrator's management console through the use of server management views. You can access the following three main types of server management views by selecting a server or network node from the ZENworks for Servers 3 namespace in ConsoleOne:
Planning Server ManagementNow that you understand the ZENworks for Servers 3 management agents and the console interface used to monitor your server's state, you need to do a little planning to get the most out of the data that ZENworks for Servers 3 provides you. This section discusses how to use the data you obtain from the ZENworks for Servers 3 console views to create a baseline document. You then find out how to use that baseline document to monitor, troubleshoot, and optimize your servers. Creating a Server Baseline DocumentYou should create a baseline document that defines the normal activity and usage of your network servers. This document is later used to identify atypical performance or problems on your servers. You can create a baseline document either from data out of the Trend view or from a server health report (see the information on health reports in Chapter 13). The following elements are vital for every baseline document:
Using a Server Baseline DocumentAfter you create a baseline document, you should keep it available and up to date. The following sections describe situations in which the baseline document can be useful. Setting Alarm ThresholdsThe most useful function of a baseline document is its capability to help you understand what thresholds to set for servers monitored by management agents. You can use the baseline document statistics to set alarm threshold values that alert you when normal server usage is being surpassed for example, the server starts running out of memory or disk space. Tracking Server UtilizationAnother useful function of a baseline document is to help you track server utilization. You can use the current and past data to evaluate the server's usage trends and understand needed configuration changes. You can, for example, use the baseline document to predict a volume running out of disk space, available cache buffers insufficient for running software, and so forth. Server TroubleshootingThe final function of a baseline document is to aid you in troubleshooting your servers. Using the typical data in the baseline document, you can recognize atypical behavior of your servers, which will help you isolate the problem. For example, suppose that a server is running out of memory. You compare the baseline document to the server's current state and notice that the only difference is that a new application is running on the server. The first step in troubleshooting is to remove the application. Displaying Server Configuration InformationUsing the ZENworks for Servers 3 namespace in ConsoleOne, you can display and view critical configuration information about your servers. You can then use this information to manage and control the servers on your managed network. The following is a list of the configuration information components and information that you can retrieve about your managed servers through the ZENworks for Servers 3 namespace:
To access the server configuration from within the ZENworks for Servers 3 namespace in ConsoleOne follow these steps:
Showing Server Summary DataDisplaying the configuration data for each individual component gives you a lot of extremely detailed and useful information. At times, however, you may want to take only a quick look at a server's configuration information. For this reason, ZENworks for Servers 3 also enables you to display a quick summary view of the most vital information about the managed server. ZENworks for Servers 3 uses a series of SNMP GET requests to the ZENworks for Servers 3 management agents to create a quick collection of summary data. That summary data is dynamically updated by ZENworks for Servers 3 as it continuously polls the server. To access the summary information about a server, right-click the server object and then select Views Summary from the pop-up menu. A screen similar to the one in Figure 12.2 appears, showing the following information about the managed server:
Figure 12.2. Server summary of a NetWare server, located in the ZENworks for Servers 3 namespace in ConsoleOne.NOTE ZENworks for Servers 3 also enables you to display similar summary data for processors, LAN adapters, disk adapters, storage devices, threads, interrupts, memory, address spaces, interfaces, connections, users, installed software, NLMs, and volumes. Viewing Trend DataTrend data is another important aspect of your servers that ZENworks for Servers 3 enables you to view and monitor. ZENworks for Servers 3 is continuously gathering data about the trends in CPU usage, memory usage, and network traffic from the managed server as it is operating. You can view the trend data from the management console in terms of current data or historically by day, week, month, or year. That trend data can be extremely useful in troubleshooting network and server issues, as well as understanding the current workload on the server. You should monitor the trend data to help with decisions on setting trend alarm thresholds, determining peak usage of the server, balancing server loads, and allocating new resources. To view the trend data from the management console, right-click the server you want to monitor and select Views Trend from the pop-up menu; a screen similar to the one in Figure 12.3 should appear. Figure 12.3. Trend Data view of a NetWare server, located in the ZENworks for Servers 3 namespace in ConsoleOne.ZENworks for Servers 3 enables you to customize the Trend Data view to give you the data's maximum use. The following sections describe how to customize the Trend Data view by displaying the legend, modifying time spans, displaying grid lines, stacking/unstacking graphs, and modifying the Trend view profile. Displaying the LegendYou must display a legend to understand the Trend Data view shown in Figure 12.3 and use it to understand the server's current status. The legend is simply a window that relates the trend data parameters used in the Trend Data view with its color of line shown on the graph. Viewing the legend helps you understand what trends are being displayed on the server so that the graph makes sense. To view the Trend Data view legend, click the Legend icon in the Trend Data view toolbar (refer to Figure 12.3). A pane similar to the one in Figure 12.4 appears. Figure 12.4. Legend window for the Trend Data view in ConsoleOne.Modifying Time SpansAfter you view the legend and understand what parameters the graph is showing you, you can modify the time spans for the trend data to best understand how the server is doing. You can modify the time span by clicking the down arrow on the toolbar of the Trend Data view and selecting one of the following time spans:
Displaying Grid LinesAnother task you can perform in the Trend Data view is to display horizontal and vertical grid lines. The grid lines make the graphs easier to read. You can turn on and off the horizontal grid lines by clicking the Horizontal Grid button on the Trend Data view toolbar. Conversely, you can turn on and off the vertical grid lines by clicking the Vertical Grid button on the Trend Data view toolbar. Stacking and Unstacking GraphsOne of the most useful ways to customize your Trend Data view is to stack and unstack the graphs. Stacking the graphs means that they are all overlaid on top of each other on a single graph with several lines for all parameters. Unstacking the graphs makes several different graphs, each with its own line for a single parameter, as shown in Figure 12.5. (Figure 12.3 shows what a graph would look like stacked.) Figure 12.5. Unstacked Trend Data view of a NetWare server, located in the ZENworks for Servers 3 namespace in ConsoleOne.To stack the graphs on top of each other, click the Stack Chart button on the Trend Data view toolbar. To unstack the graphs, click the Strip Chart button on the Trend Data view toolbar. Modifying the Trend Data View ProfileThe biggest way to modify the Trend Data view is to modify the Trend Data view profile. The Trend Data view profile is basically the set of parameters that are displayed on the Trend Data view graph. You should modify the Trend Data view profile to best fit your servers and your environment. Follow these steps to modify the Trend Data view profile:
Managing Trend SamplingsNow that you understand how to view the trend data, you need to know how to manage the way that the data is collected. ZENworks for Servers 3 enables you to modify the trend data sampling rates and thresholds used to collect the data. The following sections discuss how to use the management console to customize trend sampling to fit your network. Modifying Trend Samplings and IntervalsThe first step in managing trend sampling is to set the sampling and interval rates for trend parameters. Setting the sampling rate effectively determines the duration for which data from a particular parameter is collected by specifying the number of samples to take. Setting the interval rate determines how often data is collected from a particular parameter. Follow these steps to set the sampling and intervals for trend data parameters:
Modifying Threshold Alarm SettingsAfter you set the sampling and interval rates for the trend data parameter, you need to set the threshold alarm settings for the parameter. Modifying the threshold alarm settings for a particular parameter controls the range at which the parameter can operate before triggering an alarm. It also controls the scope of the graph in the Trend Data view. Follow these steps to modify the threshold alarm setting for a trend data parameter:
NOTE An alarm is sent the first time the rising threshold is surpassed, and if the parameter never dips back below the falling threshold, an alarm is not re-sent. In other words, for an alarm to be sent again after it has already been sent once, the parameter has to dip down below the falling threshold and then surpass the rising threshold again. Configuring Server ParametersAnother server management innovation that ZENworks for Servers 3 provides is the capability to modify server parameters without being at the server itself or having a remote management session open to it. ZENworks for Servers 3 enables you to modify the managed server's eDirectory object to make changes to its parameters. Follow these steps to modify server parameters from within ConsoleOne:
NOTE The preceding steps are a way to manually change set parameters on a server-by-server basis. If you want to do this on more than one server at a time throughout your network, you would use the Server Policy Package Set Parameters policy in the policies piece of ZENworks for Servers 3. Executing Server CommandsAnother server management innovation that ZENworks for Servers 3 provides is the capability to execute server commands without being at the server itself or having a remote management session open to it. Earlier in this chapter, you learned how to navigate the server object portion of the ZENworks for Servers 3 namespace to view configuration data. You can also use the server level of the ZENworks for Servers 3 namespace to execute server commands at the server level or below. ZENworks for Servers 3 enables you to execute the following server commands from the ZENworks for Servers 3 namespace area in ConsoleOne:
Managing Remote ServersManaging servers remotely has become an industry standard as companies have increased the number of servers, which requires large data centers. ZENworks for Servers 3 greatly enhances the capability to remotely manage servers through the addition of applications that enable you to remotely take control of the server. The following sections describe how to use the ZENworks for Servers 3 management console to remotely manage a server. Managing Remote NetWare ServersZENworks for Servers 3 includes the capability to use the RCONSOLEJ utility provided with NetWare to remotely manage a server from the management console. This enables you to manage NetWare servers based on your role in the organization and tasks assigned to you. You can use the ZENworks for Servers 3 remote management capability to perform the following role-based remote management tasks on a managed NetWare server:
Follow these steps to begin a remote management session with a NetWare server from the ZENworks for Servers 3 management console on an IP-only server:
Follow these steps to begin a remote management session with a NetWare server from the ZENworks for Servers 3 management console on an IPX-only server:
Managing Remote NT/2000 ServersZENworks for Servers 3 adds the capability to remotely manage a Windows NT/2000 Server from the management console. This enables you to manage Windows NT/2000 Servers based on your role in the organization and tasks assigned to you. You can use the ZENworks for Servers 3 remote management capability to perform the following role-based remote management tasks on a managed Windows NT/2000 Server:
Follow these steps to begin a remote management session with a Windows NT/2000 Server from the ZENworks for Servers 3 management console:
NOTE During a remote management session, the user of the Windows NT/2000 Server receives an audible signal indicating that it is being accessed. Every five seconds the user receives a visible signal displaying the name of the user accessing the remote server. These settings can be changed by selecting Edit Security Parameters from the Remote Management icon's pop-up menu on the remote server's taskbar. Optimizing Server ManagementNow that you understand how ZENworks for Servers 3 uses trend data and alarm thresholds to help you manage your servers, you need to know how to optimize the data that ZENworks for Servers 3 gathers for you. When a managed server is first started, agents for trend data, alarm thresholds, and alarm management are loaded and begin collecting data. The best way to optimize server management is to control the initial settings that are loaded on your servers. The following sections describe how to modify the configuration files that initialize the server management agents to give you tight control over the information collected and presented at the management console. Setting Initial Trend ValuesThe first configuration file you should know how to modify is the trend initialization file. This file sets the initial trends for monitoring a device. Each time a new managed device is discovered on the server, a trend file is created for it. The trend initialization file is named NTREND.INI on a NetWare server and N_NTREND.INI on a Windows NT/2000 Server. The following sections describe how to use a text editor to modify the initial trend file shown in Figure 12.12. Figure 12.12. Trend initialization file for a NetWare server.Setting the Sample IntervalThe first column in the trend initialization file is the parameter name, and the second is the sample interval. The sample interval indicates the frequency that samples of the specified parameter are collected in terms of a time interval between five seconds and one day. Evaluate each parameter to determine how often it should be sampled. If you sample too often, you run the risk of poor performance. But if you don't sample enough, you run the risk of incomplete or inaccurate information. Use the codes listed in Table 12.1 to set the sample interval for each trend data parameter.
Setting the Trend BucketsAfter you set the sample interval for the trend data parameters, you need to set the number of trend buckets in the third column. Setting the number of trend buckets determines the duration of time for which samples will be collected for the parameter. If, for example, you want to review the number of users logged in to a server for one day and you set the sample interval to be 30 minutes, you need to specify 48 trend buckets. Each bucket contains one sample taken at a 30-minute interval. After a particular time duration is exceeded for a file, the oldest trend buckets are emptied and replaced with the most recent samples. Therefore, after the duration has been reached, you will always have samples for that amount of time from the present backward. Enabling and Disabling Trend FilesThe fourth column in the trend initialization file is the Enable Trend Data option. This value can be set to either 0 or 1. Specifying 1 enables the gathering of trend data for this parameter. Specifying 0 disables the gathering of trend data for the parameter. Setting Initial Threshold ValuesAfter setting up the initial trend values, you need to specify the threshold values for alarm generation. Alarm thresholds control the values at which alarms are generated. Two values are associated with these thresholds: a rising limit and a falling limit. For rising thresholds, the rising limit is the value at which an alarm is generated for the parameter. The falling limit, for rising thresholds, is the value at which the alarm is reset. They work conversely for falling thresholds. This way, an alarm is generated only when a server goes from a good condition to a bad condition not if it simply stays in a bad state. If, for example, you have set a falling threshold on cache buffers and a falling limit of 30% and a rising limit of 50%, the server would send out an alarm if cache buffers got below 30%. If the cache buffers then wavered between 25 35%, only the one alarm would be sent. But if the servers' cache buffers climbed back up to 60% and then back down to 30%, a second alarm would be sent. Setting Rising and Falling ThresholdsThe fifth and sixth columns in the trend initialization file are the rising and falling limits, respectively. They represent a value that indicates a problem for the trend parameter and a value that indicates the trend parameter is out of trouble. You need to evaluate each parameter to determine the appropriate threshold limits and specify them in their columns. You also need to specify which type of threshold the parameter has by putting "rising" or "falling" in the Type column of the trend initialization file. Enabling and Disabling Threshold TrapsAfter you specify the limits, you can enable or disable the threshold trap by specifying 0 or 1 in the seventh column. Specifying 0 disables alarm generation for the parameter. Specifying 1 enables alarm generation for the parameter. Configuring Alarm GenerationThe next configuration file you should know how to modify is the trap configuration file, which controls alarm generation. The trap configuration file consists of keywords with associated information about alarm generation. The trap configuration file is located in the following locations on the managed servers:
The following sections describe how to modify the trap configuration file, shown in Figure 12.13, to modify the types of alarms forwarded to management consoles, community strings used for sending SNMP traps, traps to be disabled, and specific alarms that you want to prevent from being forwarded. Figure 12.13. Trap configuration file, NWTRAP.CFG, for a NetWare server.Setting the Community StringThe first thing you can set in a trap configuration file is the community string. The community string is used to generate traps and is restricted to 32 characters. The default community string is public. Setting the Time IntervalAfter setting the community string, you need to specify the time interval that alarm generation waits before issuing the next alarm. This is to prevent the network and management console from being inundated with identical alarms. The time interval can be any value between 0 and 232. If, for example, you want to set the amount of time between alarms for traps 5, 10, and 100 to 20 seconds, you would use the following command in the trap configuration file: 5 10 100 INTERVAL = 20 Configuring Alarm Security LevelsAfter you specify the time interval for alarms, you should set the severity levels for alarm generation. Each SNMP alarm has a severity level associated with it. You can specify at what severity level to generate alarms so that only those alarms are actually sent to the management console. You can use the ENABLE and DISABLE commands, with a severity level code or number, in the alarm configuration file to control which severity levels to pass through. Table 12.2 shows the severity levels for alarm generation and the associated codes for the configuration file. The following are examples of specifying severity levels in the configuration file: ENABLE SEVERITY >= MINOR DISABLE SEVERITY <= WARN
Defining Alarm RecipientsThe final configuration file you should know how to modify to optimize server management is the TRAPTARG.CFG file. The TRAPTARG.CFG file is used to send traps to third-party management consoles. It defines recipients of SNMP traps that are detected on the server. If you plan to use third-party management consoles or utilities to monitor SNMP traps, you need to add their IP addresses or IPX addresses to the TRAPTARG.CFG file for alarms to be sent to them. Follow these steps to modify the TRAPTARG.CFG file:
|