Adgenslotaddress And Adgenportaddress Mapping - ADTRAN MX2820 System Manual

MX2820 System Manual
All facilities are associated with an interface index ("ifIndex") that identifies the entity. This
ifIndex is the SNMP standard way of referring to interfaces, but the mapping method back to
slot and port can be confusing. Fortunately, this ifIndex can be translated back into a slot and
port number using two objects in the MIB designed for just that purpose. These are in the
ADTRAN generic port MIB (genport.mib), as follows:
• adGenSlotAddress
• adGenPortAddress
Each of these objects is indexed by the ifIndex. One of them defines the slot number
associated with that ifIndex. The other defines which port number on that slot is associated
with that ifIndex.
If set to sequential ifIndex method, these MIB objects must be used each time there is a need
to map an ifIndex value to a slot/port pair (because the ifIndex values can re-number if cards
are added/removed). "Fixed" mode allows the use of some math on the ifIndex value to
determine with which slot and port it is associated (for example, an ifIndex of 500017 means
mux pair 5, port 17; an ifIndex of 3 means the SCU, port 3). The MIB objects mentioned above
will also still work with these fixed ifIndex values.

adGenSlotAddress and adGenPortAddress mapping

Slot numbers are mapped in the following manner:
• Clock slot A is slot number 1, clock slot B is slot number 2
• MUX 1A is slot number 3, MUX 1B is slot number 4, MUX 2A is slot number 5, etc.
• The SCU's slot number is one greater than that of the highest MUX slot in the shelf. That
is, in a 19" shelf the last mux is 7B, which is slot number 16. Therefore, the SCU in a 19"
shelf is slot number 17. In a 23" shelf, there are 4 more mux slots, so the SCU is slot
number 21.
Port numbers are mapped as follows (Each module type has its own port number mapping).
The DS3 mux is as follows:
• port numbers 1 through 28 = T1 interfaces 1 through 28
• port number 29 = the DS3 interface
• port numbers 30 through 36 = the seven DS2 "virtual" interfaces (These virtual ports
receive ifIndex values starting at the base (500000 for mux pair 5) plus 1000. So the first
DS2 would be 501001.)
Note that each MUX module has its own slot number. When running redundant MUX
modules, and adGenSlotAddress is utilized to look up the slot number associated with an
ifIndex, the value returned is the active module in the pair. For example, for a T1 in MUX pair
2, adGenSlotAddress will give display a slot number of 5 if card A is active, or 6 if card B is
active. Both refer to the same physical port (the one connected to MUX pair 2 in the example).
If the slot and port number are known and the ifIndex is needed, use the item
"adGenIfIfIndex" in the same MIB. It provides the ifIndex.
5-134 61186003L1-1D