ASA 5505 Outside problem



Hi,
I have configured a new 5505 ASA with Security Plus licence.
I have a poblem: after some hours outside interface stop responding and the
VPN go down.
In this state i can't ping my gateway. The inside interfae work well.
With show interface I haven't any error.
I've tried to fix speed to 100 Half on switch port and ASA port but the
problem is the same.
I have't this problem an any other ASA in my company's site.
I've changed this devices with an equal devices and the problem is the same.
I suppose that isn't a configuration problem because other ASA works well.
There are some output when the ASA s in "locked" state:

ASA# sh int e0/0
Interface Ethernet0/0 "", is up, line protocol is up
Hardware is 88E6095, BW 100 Mbps
Half-Duplex(Half-duplex), 100 Mbps(100 Mbps)
Available but not configured via nameif
MAC address 0024.14ef.2a6a, MTU not set
IP address unassigned
2176 packets input, 305804 bytes, 0 no buffer
Received 90 broadcasts, 0 runts, 0 giants
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
0 L2 decode drops
5 switch ingress policy drops
1702 packets output, 224296 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 babbles, 0 late collisions, 0 deferred
0 lost carrier, 0 no carrier
0 rate limit drops
0 switch egress policy drops

ASA# s int vlan2
Interface Vlan2 "outside", is up, line protocol is up
Hardware is EtherSVI
Description: ToISP
MAC address 0024.14ef.2a72, MTU 1500
IP address xx.xx.xxx.xxx, subnet mask 255.255.255.240
Traffic Statistics for "outside":
1802 packets input, 195826 bytes
1702 packets output, 193624 bytes
19 packets dropped
1 minute input rate 0 pkts/sec, 1 bytes/sec
1 minute output rate 0 pkts/sec, 15 bytes/sec
1 minute drop rate, 0 pkts/sec
5 minute input rate 0 pkts/sec, 1 bytes/sec
5 minute output rate 0 pkts/sec, 3 bytes/sec
5 minute drop rate, 0 pkts/sec

ASA# sh ver

Cisco Adaptive Security Appliance Software Version 7.2(4)
Device Manager Version 5.2(4)

ASA up 1 hour 20 mins

Hardware: ASA5505, 256 MB RAM, CPU Geode 500 MHz
Internal ATA Compact Flash, 128MB
BIOS Flash M50FW080 @ 0xffe00000, 1024KB

Encryption hardware device : Cisco ASA-5505 on-board accelerator (revision
0x0)
Boot microcode : ?CNlite-MC-Boot-Cisco-1.2
SSL/IKE microcode: ?CNlite-MC-IPSEC-Admin-3.03
IPSec microcode : ?CNlite-MC-IPSECm-MAIN-2.05
0: Int: Internal-Data0/0 : address is 0024.14ef.2a72, irq 11
1: Ext: Ethernet0/0 : address is 0024.14ef.2a6a, irq 255
2: Ext: Ethernet0/1 : address is 0024.14ef.2a6b, irq 255
3: Ext: Ethernet0/2 : address is 0024.14ef.2a6c, irq 255
4: Ext: Ethernet0/3 : address is 0024.14ef.2a6d, irq 255
5: Ext: Ethernet0/4 : address is 0024.14ef.2a6e, irq 255
6: Ext: Ethernet0/5 : address is 0024.14ef.2a6f, irq 255
7: Ext: Ethernet0/6 : address is 0024.14ef.2a70, irq 255
8: Ext: Ethernet0/7 : address is 0024.14ef.2a71, irq 255
9: Int: Internal-Data0/1 : address is 0000.0003.0002, irq 255
10: Int: Not used : irq 255
11: Int: Not used : irq 255

Licensed features for this platform:
Maximum Physical Interfaces : 8
VLANs : 20, DMZ Unrestricted
Inside Hosts : Unlimited
Failover : Active/Standby
VPN-DES : Enabled
VPN-3DES-AES : Enabled
VPN Peers : 25
WebVPN Peers : 2
Dual ISPs : Enabled
VLAN Trunk Ports : 8

This platform has an ASA 5505 Security Plus license.

Thanks for any help


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