Cisco TCP Time Outs ASA / PIX VPN - IP Handsets

[HairySupportMonkey]

Howdy,

There is a theory around that Cisco TCP time outs can cause IP handsets to de-register from a IP Office over a VPN connection.

Can anyone concur with this notion?

we have done many IP / remote installs.

we used the new ASA5505 on two sites and having shitty issues with calls dropping , phones deregsitering etc.

: Saved
:
ASA Version 8.0(4)
!
hostname A1-Liverpool
enable password xxxxxxxxxxxxxx encrypted
passwd xxxxxxxxxxxxxx encrypted
names
!
interface Vlan1
nameif inside
security-level 100
ip address 192.168.64.254 255.255.255.0
!
interface Vlan2
description EasyNet_Liverpool
nameif outside
security-level 0
ip address xx.xx.xx.xx 255.255.255.248
!
interface Ethernet0/0
switchport access vlan 2
!
interface Ethernet0/1
!
interface Ethernet0/2
!
interface Ethernet0/3
!
interface Ethernet0/4
!
interface Ethernet0/5
!
interface Ethernet0/6
!
interface Ethernet0/7
!
ftp mode passive
access-list outside_1_cryptomap extended permit ip 192.168.64.0 255.255.255.0 192.168.65.0 255.255.255.0
access-list inside_nat0_outbound extended permit ip 192.168.64.0 255.255.255.0 192.168.65.0 255.255.255.0
!
tcp-map keepalive-timeout
!
pager lines 24
logging enable
logging asdm informational
mtu inside 1500
mtu outside 1500
icmp unreachable rate-limit 1 burst-size 1
icmp permit any inside
icmp permit any outside
asdm image disk0:/asdm-61551.bin
no asdm history enable
arp timeout 14400
global (outside) 1 interface
nat (inside) 0 access-list inside_nat0_outbound
nat (inside) 1 0.0.0.0 0.0.0.0
route outside 0.0.0.0 0.0.0.0 87.84.173.113 1
timeout xlate 3:00:00
timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 icmp 0:00:02
timeout sunrpc 0:10:00 h323 0:00:00 h225 1:00:00 mgcp 0:05:00 mgcp-pat 0:05:00
timeout sip 0:30:00 sip_media 0:02:00 sip-invite 0:03:00 sip-disconnect 0:02:00
timeout sip-provisional-media 0:02:00 uauth 0:05:00 absolute
dynamic-access-policy-record DfltAccessPolicy
http server enable
http 0.0.0.0 0.0.0.0 inside
no snmp-server location
no snmp-server contact
snmp-server enable traps snmp authentication linkup linkdown coldstart
crypto ipsec transform-set ESP-3DES-SHA esp-3des esp-sha-hmac
crypto ipsec security-association lifetime seconds 28800
crypto ipsec security-association lifetime kilobytes 4608000
crypto map outside_map 1 match address outside_1_cryptomap
crypto map outside_map 1 set pfs group1
crypto map outside_map 1 set peer xx.xx.xx.xx
crypto map outside_map 1 set transform-set ESP-3DES-SHA
crypto map outside_map 1 set security-association lifetime seconds 28800
crypto map outside_map 1 set security-association lifetime kilobytes 4608000
crypto map outside_map interface outside
crypto isakmp enable outside
crypto isakmp policy 10
authentication pre-share
encryption 3des
hash sha
group 2
lifetime 86400
telnet 0.0.0.0 0.0.0.0 inside
telnet timeout 5
ssh timeout 5
console timeout 0
dhcpd auto_config outside
!

threat-detection basic-threat
threat-detection statistics access-list
no threat-detection statistics tcp-intercept
group-policy DfltGrpPolicy attributes
vpn-tunnel-protocol IPSec
tunnel-group xx.xx.xx.xx type ipsec-l2l
tunnel-group xx.xx.xx.xx ipsec-attributes
pre-shared-key *
!
class-map inspection_default
match default-inspection-traffic
!
!
policy-map type inspect dns preset_dns_map
parameters
message-length maximum 512
policy-map global_policy
class inspection_default
inspect dns preset_dns_map
inspect ftp
inspect rsh
inspect rtsp
inspect esmtp
inspect sqlnet
inspect skinny
inspect sunrpc
inspect xdmcp
inspect sip
inspect netbios
inspect tftp
!
service-policy global_policy global
prompt hostname context
Cryptochecksum:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
: end
asdm image disk0:/asdm-61551.bin
no asdm history enable

 

[North323]

do you have more than one location? what is your phone vlan ID set at?

 

[HairySupportMonkey]

Phone vlan ID is set on default - which i think is 0

 

[North323]

is this the only location? or are there more?

 

[HairySupportMonkey]

sorry - this is the only location

so :

main office <-> ASA5505 <----VPN-----> ASA5505 <-> Remote Office

 

[North323]

ok is this avaya? do you have a switch/server in the remote office also? can you confirm the vlan ID on the phone? what happens when you change it to vlan 1?

 

[HairySupportMonkey]

yeah - avaya ip handsets.

switch is a little netgear prosafe with POE. nothing flash.

ill try vlan 1 perhaps....

cheers

 

[brianinms]

The default timeout for a translation in a ASA is 1 hour. However, if you are active on the phone that would mean you are passing traffic and wouldn't timeout. Could it be that the internet connect you are utilizing is less than ideal? If I had to guess you are probably trying to use a cable or dsl circuit.

 

[HairySupportMonkey]

both are managed xDSL connections. low contention. same provider. easynet.

i could account for dropouts and poor call quality if that was the case, but not the deregistration of handsets.

 

[brianinms]

Try a continuous ping from a workstation at the endsite to the phone system at the host. Is there a voice gateway at the end site or just merely the phone?