| Configuring the WSM using Device Manager |
The following table describes the fields on the Global SLB--General tab.
Global Server Load Balancing
Sets the state (on or off) of global SLB. The default is off.
Activates Global Server Load Balancing (GSLB) for this WSM. This option can be performed only after the optional GSLB software is activated (For more information, see "Activating Optional Software" in Web OS Switch Software 10.0 Command Reference, Part number 212778-A).
If you turn GSLB off for this WSM, any active remote sites will still perform GSLB services with each other, but will not hand off requests to this WSM.
DNS Handoffs
Enables or disables DNS handoffs to peer sites by this WSM. This should be enabled for proper GSLB operation. If disabled, whenever the WSM receives a DNS request for a configured service, it will respond only with its own virtual server IP address, regardless of performance or load considerations. This option is enabled by default.
DNS Time to Live
Sets the duration in seconds (0 to 65535, with default at 60) that the DNS response from the WSM (indicating site of best service) will remain in the cache of DNS servers. A lower value may increase the ability of the GSLB system to adjust to sudden changes in traffic load, but will generate more DNS traffic. Higher numbers may reduce the amount of DNS traffic, but may slow GSLB's response to sudden traffic changes.
HTTP Redirect
Enables or disables HTTP redirects to peer sites by this WSM. When enabled (default), this WSM will redirect client requests to peer sites if its own real servers fail or have reached their maximum connection limits. If disabled, the WSM will not perform HTTP Redirects, but will instead drop requests for new connections and cause the client's browser to eventually issue a new DNS request.
DNS Local Address Response Only
Enables or disables WSM responses to DNS queries with local virtual server IP addresses. This option is disabled by default. When enabled, the WSM will always respond to DNS queries by providing a local virtual server IP address, as long as the virtual server IP address has healthy real servers with an aggregate number of available connections equal to the total from each server's configured maximum connections, minus the server's current number of connections. When the real servers for the local virtual server IP addresses are unavailable or saturated, the WSM will respond to DNS requests using normal GSLB rules.
DNS with at Least One Address
Enables or disables DNS responses (with) at least one address. At least one IP address is included in each DNS response. Even if all remote sites cannot handle another request, the local VIP is returned in DNS response to eliminate long DNS timeouts caused by an empty response. This option is disabled by default.
Local Weight
Sets the local weight (1 - 48). The default is 1. The higher the weight value, the more connections that will be directed to the local site. The response time of this site is divided by this weight before the best site is assigned to a client. Remote site response times are divided by the real server weight before selection occurs.
Remote Site Update Interval
Sets the time in minutes (1 - 120) between Distributed Site State Protocol (DSSP) updates between this WSM and its peers. The default is 1 minute.
Minimum Site Connections
Sets the minimum number (0 - 65,535) of available site connections. The default is set at 1024. If the site's available sessions fall below this value, traffic won't be redirected to the site. A site is not eligible for more requests (such as DNS or HTTP redirects) once the number of available connections at a site drops below this threshold.
Single Address Response
Enables or disables DNS responses with only one address. At most one IP address is included in each DNS response. This option is disabled by default.
HTTP Redirect to Real Server Name
Enables or disables an HTTP redirect to a real server name. When a site redirects a client to another site using an HTTP redirect, the client is redirected to the new site's IP address. This option is disabled by default. If enabled, the client will be redirected to the domain name specified by the remote real server name plus virtual server domain name:
<remote real server name>.<virtual server domain name>
Geographic Awareness
Enables or disables geographic awareness, such as the IANA table. This option is enabled by default. If this option is disabled, all clients and sites will be assumed to exist in the same geographic region, allowing all sites to be eligible for each client.
Good Remote Site Updates
Displays the number of good remote site updates that were received.
Bad Remote Site Updates
Displays the number of bad remote site updates that were received.
See also: