When a ZENworks Management Zone includes more than one ZENworks Primary Server or Satellite (collectively referred to as servers), devices need to know which servers to contact for collection, content, configuration, and authentication purposes. These servers are referred to as closest servers.
Closest Server rules help you improve load balancing between ZENworks Servers, perform failover, and improve performance when there is a slow link between the managed devices and Servers.
Closest servers can be configured on locations, network environments, and in the Closest Server Default Rule. The Closest servers for network environment override the Closest servers for locations. When a managed device requests its list of closest server, the ZENworks system combines the server lists from the location and default rule (in that order) or network environment and default rule (in that order), and passes the combined list to the device. The managed device contacts the first server in the list and continues down the list until it is able to connect. All of the Closest Server rules are received by the managed device and are cached locally. If the location of a managed device changes, the settings and closest servers rules associated with the new location are applied to the device.
For example, assume that the device detects that it is in NetworkEnvironment1, which is associated with Location1. The closest authentication servers for each of these are defined as follows:
NetworkEnvironment1: Server4, Server5
Location: Server4, Server3
Default Rule: Server1, Server2, Server6
For authentication purposes, a device would receive the following server list. It would attempt to connect to the first one in the list, then the second, and so on until it successfully connected.
Server4 (network environment)
Server5 (network environment)
Server1 (default rule)
Server2 (default rule)
Server6 (default rule)
ZENworks allows you to configure a location or network environment to be a disconnected location or network environment. If a managed device detects itself to be in a disconnected location or network environment, it does not contact any of the ZENworks servers or Satellites until the location or network environment of the device changes to a non-disconnected location. For example, if you do not want your laptop to contact any of the ZENworks servers or Satellites when you are using it from your house, define a home location as the disconnected location by performing the following tasks while configuring the location:
Select the Exclude the Closest Server Default Rule option.
Do not configure any Closest Server rules.
You can create Closest servers for locations and network environment in one of the following ways:
Using zman commands:
For detailed information on how to create Closest servers for locations by using zman commands, see Location Commands
in the ZENworks 11 Command Line Utilities Reference or view the zman man page (man zman) on the server. For detailed information on how to create Closest servers for network environment by using zman commands, see Network Environment Commands
in the ZENworks 11 Command Line Utilities Reference or view the zman man page (man zman) on the server.
Using ZENworks Control Center: Review the following sections:
The Location Closest Servers panel in ZENworks Control Center lets you assign ZENworks Primary Servers and Satellites to the location. When a device detects that it is within the location, it contacts the defined servers. By defining the closest servers for the location, you can reduce wide area network traffic and increase ZENworks performance.
In ZENworks Control Center, click Configuration > Locations.
In the Locations panel, click the location to display its details.
Click the Servers tab.
Click Override to override the closest server settings from the location.
(Conditional) If you do not want the Closest Server Default Rule to be used in determining closest servers, select the Exclude the Closest Server Default Rule option.
Closest servers can also be configured on network environments and in the Closest Server Default Rule. When a managed device requests its list of closest server, the ZENworks system combines the server lists from the network environment, location, and default rule (in that order) and passes the combined list to the device. The managed device contacts the first server in the list and continues down the list until it is able to connect.
NOTE:If you choose to exclude the Closest Server Default Rule for a location that does not have any closest server rule configured, then the location is considered as a disconnected location.
Configure the closest servers:
Manage individual servers in any of the server lists (Collection, Content, Configuration, Imaging and Authentication):
Task |
Steps |
Additional Details |
---|---|---|
Add a server to a list |
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By default, ZENworks Servers support all functions (Collection, Content, Configuration, and Authentication). Therefore, all ZENworks Servers are available for selection in any of the server lists. Satellites, however, can be configured for specific roles (Collection, Content, Imaging, and Authentication). This has the following implications:
Satellite roles are configured in the Server Hierarchy panel on the Configuration tab. |
Reorder the list |
|
Placement in the list determines the order in which servers are contacted. The first list item (server, group, or L4 switch) is contacted first, then the second, and so forth. You can order the items in the lists differently. This allows you to spread the workload initiated by devices by placing different servers higher in one list than in the other lists. For example:
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Remove a server from a list |
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Manage server groups in any of the server lists (Collection, Content, Configuration, Imaging and Authentication).
You can use a group to randomize connections to servers. Each time the server list is sent to a device, it is randomized so that not all devices receive the same ordered list.
For example, assume the server list contains the following:
Server 1
Group 1 (Server 2, Server 3, Server 4)
Server 5
One device might receive the following list: Server 1, Server 3, Server 2, Server 4, Server 5.
Another device might receive a different list: Server 1, Server 4, Server 3, Server 2, Server 5.
In all cases, Server 1 is listed first and Server 5 is listed last, but the order of the servers in Group 1 is randomized.
You can perform the following tasks to manage server groups in any of the server lists (Collection, Content, Configuration, and Authentication):
Task |
Steps |
Additional Details |
---|---|---|
Create a server group |
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Add servers to a group |
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Reorder the list |
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Placement in the list determines the order in which servers are contacted. The first list item (server, group, or L4 switch) is contacted first, then the second, and so forth. You can order the items in the lists differently. This allows you to spread the workload initiated by devices by placing different servers higher in one list than in the other lists. For example:
|
Copy a group from one list to another list |
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If you copy a group to a list that does not already contain the group’s servers, the unlisted servers are removed from the group. For example, if Group1 includes Server1 and Server2 and you copy Group1 to a list that does not include Server1, Server1 is removed from the group. |
Remove servers from a group |
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The servers are not removed from the server list, only from the group. |
Remove a group |
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The group’s servers are not removed, only the group. |
If you have ZENworks Servers that are clustered behind an L4 switch, you can define the L4 switch and add the servers to the definition. This enables the L4 switch to continue to balance the traffic among those servers.
Manage L4 switches in any of the server lists (Collection, Content, Configuration, and Authentication):
Task |
Steps |
Additional Details |
---|---|---|
Create an L4 switch definition |
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Add servers to an L4 switch definition |
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|
Reorder the list |
|
Placement in the list determines the order in which servers are contacted. The first list item (server, group, or L4 switch) is contacted first, then the second, and so forth. You can order the items in the lists differently. This allows you to spread the workload initiated by devices by placing different servers higher in one list than in the other lists. For example:
|
Remove servers from an L4 switch definition |
|
The servers are not removed from the server list, only from the L4 switch definition. |
Remove an L4 switch definition |
|
The L4 switch definition's servers are not removed, only the definition. |
Click Apply to save your changes.
The Network Environment Closest Servers panel in ZENworks Control Center lets you assign ZENworks Primary Servers and Satellites to the network environment. When a device is located within the network environment, it contacts the defined servers. By defining the closest servers for the network environment, you can reduce wide area network traffic and increase ZENworks performance
In ZENworks Control Center, click Configuration > Locations.
In the Network Environments panel, click the network environment to display its details.
Click the Servers tab.
Click Override to override the closest server settings from the location. The resulting list includes only the servers defined for the network environment and for the Closest Server Default Rule.
(Conditional) If you do not want the Closest Server Default Rule to be used in determining closest servers, select the Exclude the Closest Server Default Rule option.
Closest servers can also be configured on locations and in the Closest Server Default Rule. When a managed device requests its list of closest server, the ZENworks system combines the server lists from the network environment, location, and default rule (in that order) and passes the combined list to the device. The managed device contacts the first server in the list and continues down the list until it is able to connect. This option excludes the default rule from being included in the server list.
NOTE:If you choose to exclude the Closest Server Default Rule for a network environment that does not have any closest server rule configured, then the network environment is considered as a disconnected network environment.
Configure the closest servers:
Manage individual servers in any of the server lists (Collection, Content, Configuration, Imaging and Authentication):
Task |
Steps |
Additional Details |
---|---|---|
Add a server to a list |
|
By default, ZENworks Servers support all functions (Collection, Content, Configuration, and Authentication). Therefore, all ZENworks Servers are available for selection in any of the server lists. Satellites, however, can be configured for specific roles (Collection, Content, Imaging, and Authentication). This has the following implications:
Satellite roles are configured in the Server Hierarchy panel on the Configuration tab. |
Reorder the list |
|
Placement in the list determines the order in which servers are contacted. The first list item (server, group, or L4 switch) is contacted first, then the second, and so forth. You can order the items in the lists differently. This allows you to spread the workload initiated by devices by placing different servers higher in one list than in the other lists. For example:
|
Remove a server from a list |
|
|
Manage server groups in any of the server lists (Collection, Content, Configuration, and Authentication).
You can use a group to randomize connections to servers. Each time the server list is sent to a device, it is randomized so that not all devices receive the same ordered list.
For example, assume the server list contains the following:
Server 1
Group 1 (Server 2, Server 3, Server 4)
Server 5
One device might receive the following list: Server 1, Server 3, Server 2, Server 4, Server 5.
Another device might receive a different list: Server 1, Server 4, Server 3, Server 2, Server 5.
In all cases, Server 1 is listed first and Server 5 is listed last, but the order of the servers in Group 1 is randomized.
Task |
Steps |
Additional Details |
---|---|---|
Create a server group |
|
|
Add servers to a group |
|
|
Reorder the list |
|
Placement in the list determines the order in which servers are contacted. The first list item (server, group, or L4 switch) is contacted first, then the second, and so forth. You can order the items in the lists differently. This allows you to spread the workload initiated by devices by placing different servers higher in one list than in the other lists. For example:
|
Copy a group from one list to another list |
|
If you copy a group to a list that does not already contain the group’s servers, the unlisted servers are removed from the group. For example, if Group1 includes Server1 and Server2 and you copy Group1 to a list that does not include Server1, Server1 is removed from the group. |
Remove servers from a group |
|
The servers are not removed from the server list, only from the group. |
Remove a group |
|
The group’s servers are not removed, only the group. |
If you have ZENworks Servers that are clustered behind an L4 switch, you can define the L4 switch and add the servers to the definition. This enables the L4 switch to continue to balance the traffic among those servers.
Manage L4 switches in any of the server lists (Collection, Content, Configuration, and Authentication):
Task |
Steps |
Additional Details |
---|---|---|
Create an L4 switch definition |
|
|
Add servers to an L4 switch definition |
|
|
Reorder the list |
|
Placement in the list determines the order in which servers are contacted. The first list item (server, group, or L4 switch) is contacted first, then the second, and so forth. You can order the items in the lists differently. This allows you to spread the workload initiated by devices by placing different servers higher in one list than in the other lists. For example:
|
Remove servers from an L4 switch definition |
|
The servers are not removed from the server list, only from the L4 switch definition. |
Remove an L4 switch definition |
|
The L4 switch definition's servers are not removed, only the definition. |
Click Apply to save your changes.