LB Methods
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Modify the GSLB configuration so that site2 is a standby DR site.

Introduce a network problem that causes the isp1 link monitor to fail.

An ISP network outage can automatically cause DR activation.

#. On gtm1.site1 navigate to: **DNS  ››  GSLB : Pools : Pool List  ››  Members : www.example.com_pool**

   https://gtm1.site1.example.com/tmui/Control/jspmap/tmui/globallb/pool/members.jsp?name=%2FCommon%2Fwww.example.com_pool&pool_type=1&identity=www.example.com_pool

   .. image:: /_static/class1/gslb_pool_persistence_flyout.png

#. Modify the "Load Balancing Method" -> "Preferred" to "Global Availability"

   .. image:: /_static/class1/gslb_pool_global_availability_details.png

   .. admonition:: TMSH

      tmsh modify gtm pool a www.example.com_pool load-balancing-mode global-availability

#. Introduce a network problem in the ISP at site1

   Log into the router and disable interface 1.6 connecting ISP1 to site1

   https://router01.branch01.example.com/tmui/Control/jspmap/tmui/locallb/network/interface/list.jsp

   .. image:: /_static/class1/router_disable_isp1_site_interface.png

   TMSH command to run on the router01 to simulate an ISP failure   

   .. admonition:: TMSH

      tmsh modify interface 1.6 disabled

#. View the effect

   Log into gtm1.site2 and observe the status of "Link" objects:

   .. image:: /_static/class1/dns_gslb1_site2_links.png

   https://gtm1.site2.example.com/tmui/Control/jspmap/xsl/gtm_link/list

   .. admonition:: TMSH

      tmsh show gtm link

#. Set the site1 isp link back up

   Log into the router and enable the interface 1.6 connecting ISP1 to site1

   https://router01.branch01.example.com/tmui/Control/jspmap/tmui/locallb/network/interface/list.jsp

   .. image:: /_static/class1/router_enable_isp1_site_interface.png

   .. admonition:: TMSH

      tmsh modify interface 1.6 enabled

Note: Even though you re-enabled the primary site1, a persistence record from the previous lab is still in place.