How to: Manage Pool and Pool Members¶
Prerequisites¶
You must have Administrator or Application Manager user credentials to manage application services. Users with Instance Manager or Auditor credentials have read-only access to application services.
Parameter details (for example, server names or addresses, pool names, and pool member addresses or names) required for the application you plan to use in the application service.
You must be managing BIG-IP Next instance. For example, refer How to: Create a BIG-IP Next instance in a VMware vSphere environment using an onboarding template.
Familiarize with pool and pool members, refer Overview: Pool and Pool Members.
Use the following topics to manage pool and pool members¶
Manage a pool¶
Use this task to specify the pools the application service will use.
Use the following steps to manage a pool:
Log in to BIG-IP Next Central Manager, click the Workspace icon next to the F5 logo, and then click Applications.
Click on the application name. The application properties display.
Click the Pools tab.
The Pools tab displays the list of pools, if no pools are available, click on Create button to start adding a pool.In the Pool Name, specify a name for the pool.
In the Service Port, specify the port number to use for this pool.
Note:
For wildcard virtual servers to accept any traffic and forward it to any pool member, you must set the Enable address translation field in the Protocols and Profiles section to enable. In the case of wildcard pool member port, address translation and port translation need to be disabled.
If the pool member port is set to 0, then it indicates that the server port translation is disabled.
Connections are reset when accessing pool members with wildcard ports and access policy enabled in Security Policies. Monitors, like HTTP, HTTPS, or TCP, need specific service ports. But with pools with wildcard members (or port 0), the monitor will wrongly report the pool member as down and fail to pass traffic. Use an ICMP monitor instead when wildcard pool members are involved.
In the Load-Balancing Mode, select a load balancing method for the pool.
The following are available load balancing modes:Round Robin: The BIG-IP Next passes each new connection request to the next endpoint in line, eventually distributing connections evenly across the array of endpoints that are load-balanced. This method works well in most configurations, especially if the equipment that you are load balancing is roughly equal in processing speed and memory.
Weighted Round Robin: The BIG-IP Next distributes connections over endpoints in a static rotation according to the ratio weights.
Least Connections (member): The BIG-IP Next passes a new connection to the endpoint having the least number of active connections.
Ratio Least Connections (member): The BIG-IP Next selects the endpoint according to the ratio of the number of active connections in each endpoint.
Ratio (session): The BIG-IP Next selects the endpoint according to the ratio of the number of entries in the persistence table.
Fastest (application): The BIG-IP Next selects an endpoint based on the least number of current sessions.
Predictive (member): The BIG-IP Next uses the ranking method used by the Observed method, where endpoints are rated according to the number of current connections. However, with the Predictive method, the BIG-IP Next analyzes the trend of the ranking over time, determining whether an endpoint’s performance is currently improving or declining. The endpoints with performance rankings that are currently improving, rather than declining, receive a higher proportion of the connections.
In the Monitor Type, select all the monitors to check the health of the pool. For more information on Monitors, refer to Monitor Management.
Note: Default monitor settings cannot be changed.
To perform CRUD operations on a pool:
Click Create to add a new pool entry.
Check the box at the Pool Name to select the pool; click Delete to delete the selected pools.
Manage pool members¶
Make sure a pool is added in the application.
Use the following steps to manage a pool member:
Log in to BIG-IP Next Central Manager, click the Workspace icon next to the F5 logo, and then click Applications.
Click on the application name. The application properties display.
Click Review and Deploy. The Instance/Locations screen opens with a list of available instance or locations or click Start Adding to specify an instance or location.
In the Members column, the number specifies the added pool members. Click the down arrow, and select Pool Members. The pool members page displays the properties and list of added pool members endpoints. If no pool members are available, click on Add Row button to start adding a pool member endpoint.
In the Name field, specify the name of the pool member.
In the Status field, select the status of the pool member. You can select Disabled or Forced Offline for maintenance, the default is Enabled.
In the IP Address, specify the IP address of the server.
To manage the priority in which traffic is distributed to pool members, set the values in Priority Group and Minimum Members Active fields.
Priority Group: This specifies the order in which traffic is distributed to grouped pool members. Pool members with higher priority group number will receive traffic before pool members with lower priority group number.
Note: If a pool member has the default priority group value of 0 (zero), it is in the lowest priority group. It only gets traffic when all pool members in higher priority groups are unavailable.
Minimum Members Active: This specifies the minimum number of pool members that must remain available in each priority group for traffic to be confined to that group. If the number of available pool members in a higher priority group falls below the specified value in Minimum Members Active field, then the traffic is distributed to both the current group and the next highest priority group pool members.
Note: If the Minimum Members Active field is set to 0 (zero), then priority grouping is disabled, and traffic is distributed among all pool members.
In the Virtual Routing & Forwarding (VRFs), choose default or non-default VRFs.
In the Action On Service Down, select the action to be taken if a target pool member becomes unavailable. The following are the available settings for this field:
None: No action is taken on existing connections, and the connection table entry is removed based on the associated profile’s idle timeout value. The BIG-IP Next sends a TCP Reset (RST) or ICMP Unreachable once idle timeout is reached. This is the default setting.
Drop: The connection table entry is removed.
Reselect: The BIG-IP Next manages established client connections by moving them to an alternate pool member without a connection teardown or setup.
Reset: The RST or ICMP messages are sent to reset active connections and remove them from the connection table. If there are available pool members for the connection, the BIG-IP Next resets and clears the active connections but sends subsequent newly arriving connections to the available pool member and does not send RST or ICMP messages.
In the Slow Ramp Time field, specify the number of seconds that the BIG-IP Next waits before sending traffic to the newly-enabled pool member. The amount of traffic is based on the ratio of how long the pool member is available compared to the slow ramp time, in seconds. Once the pool member is enabled for a time greater than the slow ramp time, the pool member receives a full proportion of the incoming traffic.
Click Save.