IPSec VPN restarts very often

[chmielniak]

Hallo,

I have defined a IPSec VPN connection with following params:

ike: 3des/sha1/dh5 Lifetime: 8 hours

ipsec: ESP/3des/sha1/dh5 Lifetime: 30 minutes (life size not set, shows 0MB)

ike gateway: main mode, DP enabled

The connection is established but in system log I see very often (every 5 sec.) tunnel is again and again down and up. We have packet lost about 0.5%.

Any ideas? I've already configured the connection from scratch again.

Jacek.

Log file:

2012/09/24 12:36:39    ipsec-key-delete    IPSec key deleted. Deleted SA: XX.XX.XX.XX[500]-YY.YY.YY.YY[500] SPI:0x8C5FC8B5/0xFFFD0AD9.

2012/09/24 12:36:39    ike-send-p2-delete    IKE protocol IPSec SA delete message sent to peer. SPI:0x8C5FC8B5.

2012/09/24 12:36:38    ipsec-key-install    IPSec key installed. Installed SA: XX.XX.XX.XX[500]-YY.YY.YY.YY[500] SPI:0xDF1F9E37/0xFFFD0ADA lifetime 1800 Sec lifesize unlimited.

2012/09/24 12:36:38    ike-nego-p2-succ    IKE phase-2 negotiation is succeeded as initiator, quick mode. Established SA: XX.XX.XX.XX[500]-YY.YY.YY.YY[500] message id:0xCFE39FEB, SPI:0xDF1F9E37/0xFFFD0ADA.

2012/09/24 12:36:38    ike-nego-p2-start    IKE phase-2 negotiation is started as initiator, quick mode. Initiated SA: XX.XX.XX.XX[500]-YY.YY.YY.YY[500] message id:0xCFE39FEB.

2012/09/24 12:36:35    ipsec-key-delete    IPSec key deleted. Deleted SA: XX.XX.XX.XX[500]-YY.YY.YY.YY[500] SPI:0xCDCD7E83/0xFFFD0AD8.

2012/09/24 12:36:35    ike-send-p2-delete    IKE protocol IPSec SA delete message sent to peer. SPI:0xCDCD7E83.

2012/09/24 12:36:34    ipsec-key-install    IPSec key installed. Installed SA: XX.XX.XX.XX[500]-YY.YY.YY.YY[500] SPI:0x8C5FC8B5/0xFFFD0AD9 lifetime 1800 Sec lifesize unlimited.

2012/09/24 12:36:34    ike-nego-p2-succ    IKE phase-2 negotiation is succeeded as initiator, quick mode. Established SA: XX.XX.XX.XX[500]-YY.YY.YY.YY[500] message id:0x756F7417, SPI:0x8C5FC8B5/0xFFFD0AD9.

2012/09/24 12:36:34    ike-nego-p2-start    IKE phase-2 negotiation is started as initiator, quick mode. Initiated SA: XX.XX.XX.XX[500]-YY.YY.YY.YY[500] message id:0x756F7417.

2012/09/24 12:36:31    ipsec-key-delete    IPSec key deleted. Deleted SA: XX.XX.XX.XX[500]-YY.YY.YY.YY[500] SPI:0xE36D50CD/0xFFFD0AD7.

2012/09/24 12:36:31    ike-send-p2-delete    IKE protocol IPSec SA delete message sent to peer. SPI:0xE36D50CD.

2012/09/24 12:36:30    ipsec-key-install    IPSec key installed. Installed SA: XX.XX.XX.XX[500]-YY.YY.YY.YY[500] SPI:0xCDCD7E83/0xFFFD0AD8 lifetime 1800 Sec lifesize unlimited.

2012/09/24 12:36:30    ike-nego-p2-succ    IKE phase-2 negotiation is succeeded as initiator, quick mode. Established SA: XX.XX.XX.XX[500]-YY.YY.YY.YY[500] message id:0x43C3E41C, SPI:0xCDCD7E83/0xFFFD0AD8.

2012/09/24 12:36:30    ike-nego-p2-start    IKE phase-2 negotiation is started as initiator, quick mode. Initiated SA: XX.XX.XX.XX[500]-YY.YY.YY.YY[500] message id:0x43C3E41C.

2012/09/24 12:36:27    ipsec-key-delete    IPSec key deleted. Deleted SA: XX.XX.XX.XX[500]-YY.YY.YY.YY[500] SPI:0x8D0BBED9/0xFFFD0AD6.

2012/09/24 12:36:27    ike-send-p2-delete    IKE protocol IPSec SA delete message sent to peer. SPI:0x8D0BBED9.

2012/09/24 12:36:26    ipsec-key-install    IPSec key installed. Installed SA: XX.XX.XX.XX[500]-YY.YY.YY.YY[500] SPI:0xE36D50CD/0xFFFD0AD7 lifetime 1800 Sec lifesize unlimited.

2012/09/24 12:36:26    ike-nego-p2-succ    IKE phase-2 negotiation is succeeded as initiator, quick mode. Established SA: XX.XX.XX.XX[500]-YY.YY.YY.YY[500] message id:0x15CF19C6, SPI:0xE36D50CD/0xFFFD0AD7.

2012/09/24 12:36:26    ike-nego-p2-start    IKE phase-2 negotiation is started as initiator, quick mode. Initiated SA: XX.XX.XX.XX[500]-YY.YY.YY.YY[500] message id:0x15CF19C6.

[mikand]

Since it takes two to tango VPN - what do you have at the other side?

And if possible, could you put one of those peers much closer to your PA to rule out any interference from the network(s) in between?

Also, how is your security policies setup for this traffic?

And is your ipsec setup on a physical interface (which perhaps goes up and down?) or a loopback interface?

[chmielniak]

I have 3 VPNs running. The problem appeared after some update in 4.1.x with all 3 connections. I can control both sides of only one connection (it's cisco router IPSec with VTI). I've just deleted the configuration on both sides and recreated it with the same parameters and it works now.

The other two VPN partners haven't change a thing and it shows above problem.

All IPSec connections are setup on the same physical interface together with normal internet traffic. I observe no problems with the interface. Security policies allow ssh connections outgoing.

How can I see what makes the connections up and down?

[ppatel]

Make sure the Crypto settings are same on both the sides and try initiating the tunnel traffic from the remote side.

Also try configuring the ipsec-crypto to DH group to "no-pfs" on both the sides. Clear the VPN tunnels on the Palo Alto side.

admin@PA> clear vpn ike-sa gateway

  <value>  clear for given IKE gateway

admin@PA> clear vpn ipsec-sa tunnel

  <value>  clear for given VPN tunnel

Try initiate the tunnel from the cisco side.

Monitor the system logs on the firewall to see the IPSEC negotiation. Check to see if the tunnel comes up.

Which version of software are you using on the firewall? There is an issue with software release 4.1.5 where after an upgrade or intermittently IPSec VPN tunnel would not come up when Palo Alto Networks firewall initiates a

connection to a Cisco ASA device. [Bug # 39884] This issue was addressed in S/w 4.1.6.

Let me know if this helps.

Regards

Parth

[chmielniak]

We have 4.1.7.

I cannot control the other side of tunnel. Those are partners, that request configuration according to their policy. I have checked the ipsec params requested. They are set correct on both sides. IPSec tunnel is established, but in log i can see those IKE deletes every ca. 10 sec. I had to disable information log on syslog.

One on VPNS ends on Fortinet. The only one VPN, that is working has no Proxy-ID defined. The other two with problems have Proxy Ids defined in IPSec tunnel.

I can see any reason for "IKE protocol IPSec SA delete message sent to peer". We experience long RTT and packet lost on those connections.

Jacek.