Cisco Cisco Packet Data Gateway (PDG)
• total-nbrs-generated
• nbrs-for-port-chunk-alloc
• nbrs-for-port-chunk-release
Port Chunk Count in show subscribers full Command Output
CSCuu74463 - [NAT] "show sub full" fails when no. of chunks is > 2500
Feature Changes
Previous Behavior: In previous releases, the show subscribers full command displayed all chunks associated
with a subscriber.
with a subscriber.
New Behavior: The show subscribers full command will display the first 2016 chunks associated with a
subscriber. The count of the actual number of port chunks will also be displayed correctly. It is recommended
to configure bigger port chunk size so that the number of port chunks allocated to a single subscriber will be
less than 2016.
subscriber. The count of the actual number of port chunks will also be displayed correctly. It is recommended
to configure bigger port chunk size so that the number of port chunks allocated to a single subscriber will be
less than 2016.
Reduction of Port Chunk Size
CSCuo77875 - [NAT] Reducing minimum port chunk size configurable to 8
Feature Changes
Reducing the port chunk size is one method of improving efficient usage of NAT IP addresses allocated to a
given Sessmgr. By increasing the number of users per NAT IP, the number of NAT IPs required to handle
the calls in a given Sessmgr could come down. This will free NAT IP addresses and can be used by other
Sessmgrs for allocation.
given Sessmgr. By increasing the number of users per NAT IP, the number of NAT IPs required to handle
the calls in a given Sessmgr could come down. This will free NAT IP addresses and can be used by other
Sessmgrs for allocation.
Prior to Release 18, the minimum port chunk size was 32 and configurable in multiples of 32, that is, 32, 64,
96, and so on. If an operator wanted to configure more than 32, it was not possible to configure 40 or 48 as
the next bigger size was only 64. If the operator required 40 ports, then two chunks each of size 32 will be
allocated. Even if only 40 ports were required, 64 ports were given. This led to under-utilization of port chunks
and NAT IP addresses.
96, and so on. If an operator wanted to configure more than 32, it was not possible to configure 40 or 48 as
the next bigger size was only 64. If the operator required 40 ports, then two chunks each of size 32 will be
allocated. Even if only 40 ports were required, 64 ports were given. This led to under-utilization of port chunks
and NAT IP addresses.
As part of the enhancement in Release 19, the minimum port chunk size configurable is reduced to 8 and the
chunk size can be configured in multiples of 8 starting 8, 16, 24, 32, and so on. The default chunk size will
still be 32. If no chunk size is configured, then the chunk size is calculated by dividing the entire NAT port
range by the number of users per NAT IP and then rounding off to the nearest multiple of 32. Session Recovery
and ICSR support are also added for this enhancement.
chunk size can be configured in multiples of 8 starting 8, 16, 24, 32, and so on. The default chunk size will
still be 32. If no chunk size is configured, then the chunk size is calculated by dividing the entire NAT port
range by the number of users per NAT IP and then rounding off to the nearest multiple of 32. Session Recovery
and ICSR support are also added for this enhancement.
Previous Behavior: The minimum supported port chunk size was 32 and the chunk size was configurable in
multiples of 32, that is, 32, 64, 96, and so on. The maximum number of chunks per user was 2016. The
maximum number of users per NAT IP address supported was 2016.
multiples of 32, that is, 32, 64, 96, and so on. The maximum number of chunks per user was 2016. The
maximum number of users per NAT IP address supported was 2016.
New Behavior: With this enhancement, the minimum port chunk size is reduced to 8. The chunk size is
configured in multiples of 8 instead of 32. The operator can configure chunk sizes starting 8, 16, 24, 32, and
so on. This enhancement provides more flexibility in deciding the actual port chunk size to be used, also
configured in multiples of 8 instead of 32. The operator can configure chunk sizes starting 8, 16, 24, 32, and
so on. This enhancement provides more flexibility in deciding the actual port chunk size to be used, also
Release Change Reference, StarOS Release 19
242
NAT Changes in Release 19
Port Chunk Count in show subscribers full Command Output