Planet Internet Telephony PBX System IPX-1900 User Manual page 44

For Static IP, both MTU and MRU are set to 1500 bytes as default value.
Note
For DHCP, both MTU and MRU are set to 1500 bytes as default value.
For PPPoE, both MTU and MRU are set to 1492 bytes as default value.
DNS Server
DNS stands for Domain Name System. Every Internet host must have a unique IP address; also they
may have a user-friendly, easy to remember name such as
the user-friendly name into its equivalent IP address. The original DNS specifications require that each
domain name is served by at least 2 DNS servers for redundancy. When you run your DNS, web, and
mail servers all on the same MAChine - if this MAChine goes down, it doesn't really matter that the
backup DNS server still works.
The recommended practice is to configure the primary and secondary DNS servers on separate
MAChines, on separate Internet connections, and in separate geographic locations.
Primary DNS Server
Secondary DNS Server
Ping From WAN
Ping is a basic Internet program that lets you verify that a particular IP address exists and can accept
requests. Ping is used diagnostically to ensure that a host computer you are trying to reach is actually
operating.
The default setting is allowed user can ping the host computer from remote site. If you disallow, the
host computer doesn't response any user who issues Ping IP address command from any remote sites.
Figure 4-6. MTU and MRU settings
Figure 4-7. DNS server settings
Sets the IP address of the primary DNS server.
Sets the IP address of the secondary DNS server.
Table 4-2. DNS server description
Figure 4-8. Ping from wan settings
www.ippbx.com. The DNS server converts
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