Cisco Cisco Packet Data Interworking Function (PDIF) Guía Para Resolver Problemas
Troubleshooting
Troubleshooting the PDIF ▀
Cisco ASR 5000 Series Packet Data Interworking Function Administration Guide ▄
OL-22963-01
The PDIF can detect the event if DPD is configured on the PDIF and if the failure lasts long enough for DPD to trigger
a session teardown. The PDIF has no way to actively determine that the WiFi or access networks have failed if DPD is
not configured. The behavior now becomes similar the that described in “MS Temporarily Roams Away From WiFi
Access Point.”
a session teardown. The PDIF has no way to actively determine that the WiFi or access networks have failed if DPD is
not configured. The behavior now becomes similar the that described in “MS Temporarily Roams Away From WiFi
Access Point.”
Total PDIF Failure
The MS can not detect a PDIF failure without DPD. It can only detect the failure when it no longer sends traffic or when
some timers start to expire.
some timers start to expire.
However, if DPD is configured on the MS, the MS can detect the PDIF failure. When the PDIF does not respond to the
DPD exchange request, the MS declares the IPSec session failed and so attempts to establish a new IPSec session.
DPD exchange request, the MS declares the IPSec session failed and so attempts to establish a new IPSec session.
Since the primary PDIF is incapable of establishing a new IPSec session with the MS, it attempts to establish an IPSec
session with a secondary PDIF if there is one available, with an IP address provided by the DNS server.
session with a secondary PDIF if there is one available, with an IP address provided by the DNS server.
Assuming a secondary PDIF is available, the MS establishes a new IPSec session. Since the primary PDIF has failed
completely, it is assumed that the old IPSec session from the MS has been lost. If this is not the case, the primary PDIF
tears down the IPSec session with the MS when one of the following events happens:
completely, it is assumed that the old IPSec session from the MS has been lost. If this is not the case, the primary PDIF
tears down the IPSec session with the MS when one of the following events happens:
The MS receives mobile IP revocation from the HA.
The IPSec session timer expires.
The inactivity timer expires.
Partial or Transient PDIF Failure
The MS can not detect a PDIF failure without DPD. It can only detect the failure when it no longer sends traffic or when
some timers start to expire.
some timers start to expire.
However, if DPD is configured on the MS, the MS can detect the PDIF failure. When the PDIF does not respond to the
DPD exchange request, the MS declares the IPSec session failed and so attempts to establish a new IPSec session.
DPD exchange request, the MS declares the IPSec session failed and so attempts to establish a new IPSec session.
If the primary PDIF is capable of establishing a new IPSec session because the failure was partial or transitory, the MS
establishes a new IPSec session with the original PDIF. When the PDIF determines that the IMSI of the MS is already
registered to another IPSec session, it establishes the new session and then clears the old one.
establishes a new IPSec session with the original PDIF. When the PDIF determines that the IMSI of the MS is already
registered to another IPSec session, it establishes the new session and then clears the old one.
If the primary PDIF is incapable of establishing a new IPSec session, the MS attempts to establish an IPSec session to
the secondary PDIF provided by the DNS server. Assuming this secondary PDIF is available, the MS establishes a new
IPSec session.
the secondary PDIF provided by the DNS server. Assuming this secondary PDIF is available, the MS establishes a new
IPSec session.
If the old IPSec session on the primary PDIF still exists despite the failure, the primary PDIF tears down the IPSec
session to the MS when one of the following events happens:
session to the MS when one of the following events happens:
The MS receives MIP revocation from the HA.
The IPSec session timer expires.
The inactivity timer expires.