TMS zl Management and Configuration Guide ST.1.1.100430

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Troubleshooting
Troubleshooting the TMS zl Module in Routing Mode
To ensure that the TMS zl Module can resolve domain names successfully,
complete the following steps:
a. Ensure that your DNS settings are configured correctly so that the
TMS zl Module can resolve the DNS name. Complete one of the
following:
– In the Web browser interface, click Network > Settings > General.
– At the CLI, enter:
hostswitch (tms-module-C)# show ip dns
b. Ensure that an access policy allows traffic from the TMS zl Module to
the zone that contains the DNS server. Complete one of the following;
– In the Web browser interface, click Firewall > Access Policies >
Unicast and locate the policies for the source zone and destination
zone.
– At the CLI, enter:
hostswitch (tms-module-C)# show access-policy
c. Ensure proper connectivity between the TMS zl Module and the DNS
server by completing one of the following:
– In the Web browser interface, click System > Utilities > Ping and
enter the DNS server’s IP address for the Hostname/IP Address.
– At the CLI, enter:
hostswitch (tms-module-C)# ping <IP_address>
d. At the CLI, enter:
hostswitch (tms-module-C)# nslookup <domain name>
If DNS-related problems seem to occur sporadically, make sure the DNS
infrastructure is up all the time and set up a process so that you are notified
if the DNS server goes down or becomes unavailable.
To follow best practices, you should consider using other types of address
objects in your access policies. Alternately, place access policies that use
domain names at the end of the access policy list. This allows you to
mitigate the effect of DNS-related failures (if one should occur).