Доброго времени суток уважаемые специалисты.
Возникла вот такая вот проблема, перерыл много информации но для себя ответа не нашел, прошу судить не строга так, как только начинаю администрировать Cisco.
Суть :
Имеються два провайдера, при переключении на другого провайдера, в случае пропажи первого происходит crash.

Crashinfo ^
Mar 16 12:37:00: %ALIGN-3-SPURIOUS: Spurious memory access made at 0x4399CDB0  reading 0x0
Mar 16 12:37:00: %ALIGN-3-TRACE: -Traceback= 0x4399CDB0 0x42ECD2C0 0x42ECB6AC 0x42ECBC90 0x42ECAC94 0x42ECC380 0x42ECBBB4 0x42ECCB68
Mar 16 12:37:00: %ALIGN-3-TRACE: -Traceback= 0x4399CDB8 0x42ECD2C0 0x42ECB6AC 0x42ECBC90 0x42ECAC94 0x42ECC380 0x42ECBBB4 0x42ECCB68
Mar 16 12:38:57: %LINK-3-UPDOWN: Interface Virtual-Access4, changed state to up
Mar 16 12:38:58: %LINEPROTO-5-UPDOWN: Line protocol on Interface Virtual-Access4, changed state to upCMD: 'clear ip nat trans forced' 12:42:28 UTC Tue Mar 16 2010

Mar 16 12:42:30: %CRYPTO-4-RECVD_PKT_INV_SPI: decaps: rec'd IPSEC packet has invalid spi for destaddr=*, prot=50, spi=0x2F8F9A9C(797940380), srcaddr=*
Mar 16 12:48:27: %CRYPTO-4-RECVD_PKT_INV_SPI: decaps: rec'd IPSEC packet has invalid spi for destaddr=*, prot=50, spi=0xA56B3D93(2775268755), srcaddr=*
Mar 16 12:55:33: %CRYPTO-4-RECVD_PKT_INV_SPI: decaps: rec'd IPSEC packet has invalid spi for destaddr=*, prot=50, spi=0xF1894AA3(4052306595), srcaddr=*

12:55:43 UTC Tue Mar 16 2010: Address Error (load or instruction fetch) exception, CPU signal 10, PC = 0x400CC700

При  'clear ip nat trans forced'  система уходит в ребут…

show version
Cisco IOS Software, 2800 Software (C2800NM-ADVENTERPRISEK9-M), Version 12.4(11)T, RELEASE SOFTWARE (fc2) Technical Support: http://www.cisco.com/techsupport Copyright (c) 1986-2006 by Cisco Systems, Inc.
Compiled Sat 18-Nov-06 17:16 by prod_rel_team

ROM: System Bootstrap, Version 12.4(13r)T, RELEASE SOFTWARE (fc1)

vali uptime is 1 hour, 26 minutes
System returned to ROM by bus error at PC 0x400CC700, address 0xB0D0AFD at 12:55:43 UTC Tue Mar 16 2010 System restarted at 12:57:20 UTC Tue Mar 16 2010 System image file is "flash:c2800nm-adventerprisek9-mz.124-11.t.bin"

...
Cisco 2821 (revision 53.51) with 249856K/12288K bytes of memory.
Processor board ID FCZ123071ZK
2 Gigabit Ethernet interfaces
1 Virtual Private Network (VPN) Module
DRAM configuration is 64 bits wide with parity enabled.
239K bytes of non-volatile configuration memory.
62720K bytes of ATA CompactFlash (Read/Write)

Кусочек конфига :
Конфиг :
event manager applet dataLINE_switch
event track 1 state up
action 1.0 cli command "enable"
action 2.0 cli command "clear ip nat trans forced"
event manager applet alternet_switch
event track 2 state up
action 1.0 cli command "enable"
action 2.0 cli command "clear ip nat trans forced"

Сразу каснусь еще одного вопроса:
В логах имееться дело вот такому :
Mar 17 14:16:56 192.168.0.11 565: Mar 17 12:16:55: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.1: the fragment table has reached its maximum threshold 16
Mar 17 14:17:26 192.168.0.11 566: Mar 17 12:17:25: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.1: the fragment table has reached its maximum threshold 16
Mar 17 14:17:56 192.168.0.11 567: Mar 17 12:17:55: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.1: the fragment table has reached its maximum threshold 16
Mar 17 14:18:28 192.168.0.11 568: Mar 17 12:18:27: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.1: the fragment table has reached its maximum threshold 16
Mar 17 14:19:02 192.168.0.11 569: Mar 17 12:19:01: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.1: the fragment table has reached its maximum threshold 16
Mar 17 14:19:34 192.168.0.11 570: Mar 17 12:19:33: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.1: the fragment table has reached its maximum threshold 16
Mar 17 14:20:04 192.168.0.11 571: Mar 17 12:20:03: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.1: the fragment table has reached its maximum threshold 16
Mar 17 14:20:50 192.168.0.11 572: Mar 17 12:20:49: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.1: the fragment table has reached its maximum threshold 16
Mar 17 14:21:21 192.168.0.11 573: Mar 17 12:21:20: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.1: the fragment table has reached its maximum threshold 16
Mar 17 14:21:51 192.168.0.11 574: Mar 17 12:21:50: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.1: the fragment table has reached its maximum threshold 16
Mar 17 14:22:22 192.168.0.11 575: Mar 17 12:22:21: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.1: the fragment table has reached its maximum threshold 16
Mar 17 14:22:53 192.168.0.11 576: Mar 17 12:22:52: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.1: the fragment table has reached its maximum threshold 16
Mar 17 14:23:24 192.168.0.11 577: Mar 17 12:23:23: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.1: the fragment table has reached its maximum threshold 16
Mar 17 14:23:56 192.168.0.11 578: Mar 17 12:23:55: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.1: the fragment table has reached its maximum threshold 16
Mar 17 14:24:32 192.168.0.11 579: Mar 17 12:24:31: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.1: the fragment table has reached its maximum threshold 16
Mar 17 14:26:42 192.168.0.11 21: *Mar 17 12:40:59: %LINEPROTO-5-UPDOWN: Line protocol on Interface Tunnel12, changed state to down
Mar 17 14:26:42 192.168.0.11 22: *Mar 17 12:40:59: %LINEPROTO-5-UPDOWN: Line protocol on Interface Tunnel13, changed state to down

Интерфейс валиться и идет переключение на другова провайдера, а тут  'clear ip nat trans forced'  система уходит в ребут…
Замкнутый круг.

Вопрос следующий. Возможно ли исправить проблему падения цыски при 'clear ip nat trans forced'  .
И можна ли по подробнее услышать о virtual reassembly, на даный момент его пришлось отключить на интерфейсе .

За ранние спасибо.