June 2018
482 Legrand PDU User Guide
Role of a DNS Server
As Internet communications are carried out on the basis of IP addresses, appropriate DNS server settings
are required for mapping domain names (host names) to corresponding IP addresses, or the Legrand PDU
may fail to connect to the given host.
Therefore, DNS server settings are important for external authentication. With appropriate DNS settings, the
Legrand PDU can resolve the external authentication server's name to an IP address for establishing a
connection. If the SSL/TLS encryption is enabled, the DNS server settings become critical since only fully
qualified domain name can be used for specifying the LDAP server.
For information on external authentication, see Setting Up External Authentication (on page 173).
Cascading Troubleshooting
Any accessibility problem occurred on one of the devices in the cascading chain may result in failure to
access all downstream slave devices that are connected to it.
Possible Root Causes
The following lists the network accessibility issues and possible root causes.
You can always troubleshoot the software settings by connecting the Legrand PDU to a computer if network
access to that Legrand PDU fails. See Connecting the Legrand PDU to a Computer (on page 30).
Symptom Probable cause
Failure to access the master
device
Anything below is lost on the master device:
Network connection
Power supply
Anything below is disabled on the master device:
The Ethernet or wireless interface
IPv4 or IPv6 settings
In the Port Forwarding mode, related settings are
incorrectly configured on the master device.
The master device's role is incorrectly set to 'Slave'.
The interface where the network is connected is
incorrectly set as the downstream interface.
For the wireless networking, one of the following issues
occurs:
The USB wireless LAN adapter attached to the
master device is not the Raritan USB WIFI LAN
adapter. See USB Wireless LAN Adapters (on page
24).
The wirele
ss LAN configuration is not supported. See
Supported Wireless LAN Configuration (on page
24).
The installed CA certificate chain
contains any
certificate that has expired or is not valid yet.
To Next Page
Loading...
