Network - Help
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Network - Help |
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Other Help Topics: Main Help Page Address Space Help |
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Summary
Actions on Address Spaces |
Summary:The Network record defines and groups address spaces, determines access to address spaces, assigns dynamic DHCP addresses and sets DHCP options. Generally, only Networking Systems and MedIT have access to Network records.Associated Fields:Name - This name is actually used in DNS. The name must obey Internet naming standards and be unique within its domain. Under Internet naming standards, the name can contain only alphanumeric characters and the hyphen. No leading or trailing hyphens are allowed. The name must contain at least one letter. Groups - Users that are members of these Groups can modify this Network if they have Network record access. Comment - Useful information of your own can be added here. It is searchable from the Full Search page. Only printable characters are valid for comments. The printable character set consists of the alphabet, any numbers, all punctuation and spaces. For example, the carriage return is a non-printable character. DHCP Service - Currently, there is only one possible selection, dhcp_service. In the future, different Networks may use different DHCP servers. DHCP Options - List desired DHCP options here. For more information,
see DHCP options.
Address Space - This section has several
fields for each address space:
Address Space - Address spaces are designated in
"slash" format. For example, 171.64.20.0/24 designates
an address space starting at 171.64.20.0 with a
/24 Network prefix. Other acceptable input formats follow: Low Reserve - Number of IP addresses at the bottom of the
range that can only be assigned explicitly by a User with All Records access (i.e., gods).
This number does not include the network address. For instance, if the low reserve is
2 in address space 171.64.20.0/24,
the first assignable address by a regular User is 171.64.20.3.
When creating an address space, the low reserve is set to 1
by default. This can be changed before saving. High Reserve - Number of IP addresses at the top of the range that
can only be assigned explicitly by a User with All Records access (i.e., gods). This number does
not include the broadcast address. For instance, if the high reserve is
3 in address space 171.64.20.0/25,
the last assignable address by a regular User is 171.64.20.123.
(171.64.20.127 is the broadcast, the addresses between the assignable
address and the broadcast address are reserved). When creating an address space, the high
reserve is set to 0 by default. This can be changed before saving. Prefix Box, Split and Join - These two (2) items are used
only during modify operations. The prefix box specifies the new prefix to be used. The
split/join specify the operation. A split or join cannot involve more than sixteen (16)
address spaces. In other words, the new network prefix cannot be more than six (6) greater
or less than than the old network prefix. For more on splitting
and joining address spaces, please see below. Address Space Group - Users that are members of these Groups
can assign IP addresses within this address space if they have Node record rights. Address Space DHCP Options - This is a list of DHCP options
that apply to this address space. See DHCP Options for DHCP
option list. Address Space Comment - Useful information can be added here.
Searchable in Full Search. Dynamic DHCP Addresses - These addresses are used for roaming
hosts (hosts with Roaming DHCP enabled). Each address is automatically assigned a name and
is flagged active. These can be modified. See below for more about
Dynamic DHCP addresses. Created By / Created Date - Person who created this record and the
date it was created. Modified By / Modified Date - Person who last modified this record
and the date of last modification
General Notes Because of database limitations, some care must be taken
when modifying address spaces. Unsaved address spaces cannot be split
or joined because the results are unpredictable. To save an address space,
hit the Save button for the entire Network.
The difference between the new and old network prefixes
cannot be greater than six (6). That is to prevent operations like spitting
a /8 Network into /29 Networks which severely affects performance of the
NetDB system.
Note that any actions on address spaces do not affect existing
address assignments.
Adding and Configuring Address Spaces
To delete an address space, uncheck the box next to the
address space range. Save changes. Address spaces with addresses assigned to
nodes cannot be deleted.
To move an address space, To split an address space, enter the new network prefix
and click the "Split/Join" button.
To shrink an address space,
Expanding means making a bigger address space by adding
unallocated address ranges to an existing address space. To expand an
address space, enter in the new network prefix and click on "Split/Join".
For example, if address space 171.64.20.0/24 is too small and
171.64.21.0/24 has not been allocated, one can expand the address
space to 171.64.20.0/23.
Joining means making a bigger address space out of existing
address spaces. To join or expand an address space, all the address ranges
must exist in the same Network record. If the address spaces are distributed
among several Networks, the address ranges must be moved into the same
Network. For example, to join 171.64.20.0/25 and
171.64.20.128/25 into one Network, make sure both address spaces
are on the same Network. Then enter "24" into the new network prefix
box of either network prefix box and select "Split/Join". The page will
return with the new address space. Save changes. Dynamic DHCP addresses are handed out to roaming hosts
and can only be added after address spaces are created.
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