ITEM: AT0150
NetView - What is ipmap?
Question:
Question:
What is ipmap?
ipmap is a computer program that is part of NetView for AIX. ipmap is
always automatically started when the User Interface is started, and it
is always automatically stopped when the User Interface is stopped. You
will never need to manually start or stop the ipmap application.
ipmap is an important application because there are two components of
NetView for AIX that must "talk" to each other, but yet speak different
"languages".
The two different components that ipmap helps converse are the User
Interface (ovw) and the netmon daemon. The User Interface is the program
that displays information on the screen and processes user input. netmon
is a NetView for AXI daemon that discovers all of the IP devices in your
network and polls these devices for status and configuration changes.
ipmap helps the User Interface and netmon talk to each other so that the
pictures on the screen match the information in the IP Topology database
(the database where netmon stores information on IP devices in your
network).
So, it is helpful to think of ipmap like an "interpreter" or a "translator".
In most conversations between two people, the conversation is "two-way",
which means that both people get to take turns talking and listening.
The conversation between ovw and netmon is the same way. Below, we see
when ovw says something that netmon needs to know about, and when netmon
says something that ovw needs to know about:
When the User Interface says something that netmon needs to know about:
* When the user deletes or adds an object with the User Interface
* When the user manages or unmanages an object with the User Interface
* When the user moves (cuts and pastes) a node from one segment
to another
Whenever ther user does something through the user interface that
would affect the information in the IP Topology database, ipmap
makes the necessary changes to the IP Topology database. For instance,
when a user deletes an object from the map, ipmap must ensure that
the object is deleted from the IP Topology database. If ipmap did
not do this, then netmon would continue to poll the device for status
and configuration changes, even though the user has removed the picture
of the device (the symbols) from the map.
When netmon says something that the User Interface needs to know about:
* When netmon discovers or deletes an object
* When netmon moves a node from one segment to another
* When netmon changes the status of an object
Whenver netmon discovers that the state of the network has changed,
netmon changes the appropriate values in the IP Topology database.
ipmap takes this new information and tells ovw how to display it.
For instance, when the netmon daemon discovers a new device, netmon
creates a record of that device in the IP Topology database. ipmap
reads that record, and then tells the User Interface to draw the
appropriate icons and/or connections on the map.
Summary:
ipmap's main job is to ensure that the IP Topology database and the
pictures displayed by the User Interface match.
****************************************************************************
What is a Map?
As stated above, ipmap tells the User Interface which icons, connections
and submaps to create, based on the information in the IP Topology
database. All of these graphical elements (the symbols and submaps)
taken together are called a "Map". A Map is stored in ovw's own Map
Database, which is separate from the IP Topology database. The Map
Database is persistent, which means that the Map Database is stored
on disk, and continues to exist even when the User Interface is brought
down.
Summary:
The Map is the collection of graphical elements (symbols and submaps)
that represent things in your network.
****************************************************************************
What is Synchronization?
When you bring up a previously created Map with the User Interface, ovw
reads the Map Database and draws the map accordingly. At this point,
the map will look exactly like it did when this map was last viewed.
However, the netmon daemon (the daemon that monitors the state of network)
can run all of the time, even when the User Interface is not running. This
means that netmon can be changing the contents of the IP topology database
when the User Interface is not running. Therefore, it is possible that
when you bring up a Map with the User Interface, the picture on the
screen may not match the information in the IP Topology database.
This is where ipmap comes in. When you bring up a Map with the User
Interface, ipmap gets a list of everything that has changed in the IP
Topology database since this Map was last closed (the last time the Map
was viewed and changed by ipmap/ovw). At this point, the "Synchronization"
message appears, and ipmap starts figuring out how to change the Map
to make it reflect all of the changes that have been in the IP Topology
database. ipmap tells ovw how to change the Map (ipmap does this through
ovw API calls). Once ipmap has finished updating the map, the
"Synchronization" message is removed.
During the Synchronization process, some actions cannot be performed with
the User Interface, because ipmap is busy updating the databases.
Depending on how many changes have been made to the IP Topology database,
the Synchronization process can take anywhere from a few seconds to
several minutes.
Summary:
Synchronization means that ipmap is resolving differences between the
IP Topology database and the Map.
****************************************************************************
How does ipmap decide how the Map will look?
There are five basic decisions that ipmap must make when telling ovw
how to draw a map. These four decisions are:
1) What symbol(s) will ipmap use to represent an object in the IP Topology
database?
2) Where will ipmap tell ovw to put these symbols?
3) What symbol label will ipmap assign to a symbol?
4) How does ipmap decide how the status of an object is represented?
5) Which icon symbols does ipmap connect together with connection
symbols?
These are complex questions, so let's consider them one at a time.
****************************************************************************
What symbol(s) will ipmap use to represent an object in the IP Topology
database?
ipmap picks a symbol type based upon the type of object in the IP Topology
database. The following table associates object types with symbol types:
Object Type Default Symbol
-------------------+------------------------------------------------------
Location/Internet These objects are created by users, and the symbol
type is the symbol that user specifies.
Network IP Map always uses the "IP Network" symbol to
represent Networks, unless the network is a serial
network, in which case a connection symbol (a line)
is used.
Segment The valid segment types that IP recognizes are
Token Ring, Bus, Star, and Serial.
Computer/Connector ipmap checks the /usr/OV/conf/C/oid_to_sym file
to determine which type of symbol to use for
node symbols. This file associates SNMP
sysObjectIds with particular symbol types.
Interface Card If the card is not serial, then the IP Card is
used.
If the card is serial, then the Serial Card is
used.
Connection The default connection symbol is just a straight
unbroken line.
****************************************************************************
Where will ipmap tell ovw to put these symbols?
ipmap creates something called the "submap hierarchy". The submap
hierarchy is a set of rules that governs:
1) What "type of submap" you get when you double-click on certain type
of object
2) What type of symbols are allowed on what type of submap.
>From these rules, ipmap creates a "tree" of submaps. As you traverse
down the tree, you see a more specific view of your network.
The following chart shows what types of submaps there are, and what
types of symbols are allowed on that submap type:
+---------------------------------------------------------------+
| ipmap's Submap Hierarchy |
+--------------------------+------------------------------------+
| Submap | Symbols Supported |
+--------------------------+------------------------------------+
| Root submap | IP Internet |
+--------------------------+------------------------------------+
| Location or Internet | Location |
| | Internet |
| | IP network |
| | Connector (for example, a |
| | gateway) |
| | Connection |
+--------------------------+------------------------------------+
| Network | Segment |
| | Connector (for example, a |
| | gateway) |
| | Connection |
+--------------------------+------------------------------------+
| Segment | Node (for example, computers |
| | and connectors) |
| | Backbone |
| | Connection |
+--------------------------+------------------------------------+
| Node | Interface card |
+--------------------------+------------------------------------+
So, at the top level, there is an IP Internet symbol. Clicking on
that, you will see an Internet submap, which could have other
Internets and Locations, as well as Gateway and Network Symbols.
Clicking on one of the Networks, you would find Segment symbols,
as well as other types connectors (like gateways, hubs, bridges, and
repeaters). Clicking on the Segment, you would see a backbone symbol
(perhaps representing an actual token ring medium) with many node
symbols connected to it. Finally, clicking on the Node symbol, you
would see a node submap, which would contain Interface card symbols.
The Interface Card symbols do not, by default, have child submaps.
****************************************************************************
What symbol label will ipmap assign to a symbol?
The label assigned to a given symbol depends on the type of symbol. Below
is listed each symbol type, and the default label that is displayed:
Symbol Type Default Label
-------------------+------------------------------------------------------
Location/Internet These symbols are created by users, and the label
is the label that user specifies.
Network If there is an entry for that network in the
/etc/networks file, then the network name is used.
If there is no entry, then the IP address of network
is used.
Segment If created by User, then the selection name specified
by user is used.
If discovered by netmon, then the label is
the word "Segment" with a number at the end.
Ex: "Segment3"
Computer/Connector If the first IP address discovered for that node
is resolvable, then the first word of the hostname
is the label.
If no hostname is available, then the first IP address
discovered for that node is the label.
Interface Card If SNMP information is availabe, then the ifDescr
object in the MIB is used for the label.
If no SNMP information is available, the the IP address
of the card is used.
Connection By default, there are no labels drawn for connection
symbols.
If this is overridden by the user, then the IP address
is used.
****************************************************************************
How does ipmap decide how the status of an object is represented?
There are some IP symbols whose status is explicitly set by the ipmap
application, and there are some symbols whose status is calculated by
ovw without ipmap's help. A symbol's "Status Source" dictates who
(an application or ovw) sets the status of an object.
If a symbol has "Object" or "Symbol" status source, then an OVw application
(like ipmap) sets the status of the symbol. If a symbol has "Compound"
status source, then ovw calculates the status of the symbol, based upon the
status of the symbols in the symbol's child submap. Below is a summary of
which symbols get which status source:
Object Status Source
* Symbols that correspond to interface card objects get
object status source. In other words, interface card
symbols, and connection symbols that correspond to
interfaces (NOT networks), get object status source.
Symbol Status Source
* All node symbols (Connectors, Servers, and Computers)
on a network and segment submaps.
Compound Status Source
* All other symbols on your IP submaps should have
compound status source by default. This includes,
but is not limited to
** all network and segment symbols
** all location and internet symbols
** all node symbols on the internet and location
submaps
It is often asked why there are these three types of Status Source.
Here is the reasoning behind each type of status source:
Object Status Source:
Sometimes, an application would like all symbols corresponding to a
given object to have the same status, and the application only wants
to make one OVw API call to change all of the symbols for that object.
This is the reason for the Object Status Source. An application can
use a single OVw API call OVwSetStatusOnObject to set simultaneously the
status of all symbols for a given object.
This is why Interface cards have Object status source. An Interface
card only has one status (it is either up or it is down), and ipmap
only wants to make a single call to set the status on the map. ipmap
does not wish to set the status for every possible symbol that might
represent that interface card.
Symbol Status Source:
Sometimes, an application wants to have different symbols for the same
object have different status colors. For example, you might want to
have different "views" of an object, with a different symbol representing
a different view of the object. From one "point of view", an object
could be down, but from another, the object could be up.
This is why ipmap gives gateway symbols on segment and network submaps
symbol status source. Imagine a gateway that has two interface cards,
one in each of two networks. One of the cards is up, and one of the
cards is down. The gateway, as represented in the network that has the
down card, has down status, but the gateway symbol in the network that
has the up card is up.
Compound Status Source:
Sometimes, an application wants to create a symbol but have the User
Interface calculate and set the status of the symbol. For instance,
a network itself is not really ever up or down... actually, there are
just devices in that network, and the devices can either be reachable
or not reachable. So really, the state of the network is just the
"average" state of all of the devices within it.
This is what compound status is for. Compound status just "averages"
the status of all of the symbols in the child submap. This is why
networks, segments, locations, internets, and gateways (at the top
level view only) have compound status source.
****************************************************************************
How does ipmap connect symbols together?
ipmap draws connection symbols (lines) between different icon symbols.
These connection symbols can represent one of three things:
1) An interface card that:
a) connects a node to a network, segment, segment backbone, or
location/internet symbol
b) connects a location/internet to a network or another
location/internet symbol
2) A serial network that:
a) connects a gateway to another gateway or location/internet symbol
b) connects a location/internet to another location/internet symbol
3) A group of the above (a connection symbol that actually represents
a group of connection symbols is called a "meta-connection")
In most cases, a connection symbol will represent an interface card.
For example, if you see a gateway that is connected to a network symbol,
click on the connection symbol to highlight it. Now double-click on the
gateway symbol to see its interface cards. You should see one of
the cards highlighted. This connection symbol represents this card.
The card and the connection symbol will be the same color (status) unless
the user specifies otherwise.
****************************************************************************
Are the rules that ipmap uses to create the map carved in stone, or can
the user change them?
The user can change some of them. Here are the things that can be
changed, and how the user can change them:
* Symbol Type (for node symbols and serial connection symbols only)
The user can change which symbols are created for which nodes
by changing the /usr/OV/conf/C/oid_to_sym file. This file
contains an association of which symbol types are associated
with SNMP sysObjectIds.
The user can also manually change the symbol type for any node
through the User Interface, but this is generally not recommended,
because this function can change fields that are listed in the
Object Database.
In addition, through the File..Describe Map menu, the user can
change the way that serial connection symbols are drawn. They
can be drawn as:
* Solid lines
* Dotted lines
* Dashed lines
* "DotDash" lines
* Where Symbols Are Drawn (for node symbols only)
As stated above, Where symbols are drawn depends on whether or
not a symbol is considered to be a Gateway, Hub, Bridge, or
Multiport Repeater. The user can change which nodes are
which type by changing the /usr/OV/conf/oid_to_type file. The
"G", "B", and "H" flags can be used to associate certain SNMP
sysObjectIds with certain object types.
* Symbol Labels (for interface cards only)
Through the File..Describe Map menu, you can specify how Interface
Card labels are displayed. The user can choose between:
* ifDescr (the interface card description in the MIB)
* IP Address
* Physical address
* Status Source of Symbols
Through the File..Describe Map menu, you can specify that all node
symbols have the status source of "Compound". In addition, you
can tell ipmap to not set the status of connection symbols. Finally,
you can also turn off ipmap's status updates completely.
Support Line: NetView - What is ipmap? ITEM: AT0150
Dated: January 1996 Category: N/A
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