Hello,
I'm cross posting this from the OpenSwan mailing list, in case someone here can help.
We have two sites connected via OpenSwan 2.6.32-9 on CentOS 5, sharing 6 /24 subnets each (so 12 in total).
The problem we're having is completely randomly, be it in the middle of the day, or in the middle of the night (so I don't believe it's traffic related), certain (and sometimes all) routes will drop. They usually recover after a few minutes, but it's still long enough for our monitoring to detect downtime.
The configuration we have on each device is:
conn site-a keyingtries=0 keylife=1h ikelifetime=8h left=1.1.1.1 right=2.2.2.2
leftsubnets={x.x.x.x/24,x.x.x.x/24,x.x.x.x/24,x.x.x.x/24,x.x.x.x/24,x.x.x.x/24}
rightsubnets={x.x.x.x/24,x.x.x.x/24,x.x.x.x/24,x.x.x.x/24,x.x.x.x/24,x.x.x.x/24} pfs=yes auto=start authby=secret dpddelay=30 dpdtimeout=120 dpdaction=hold phase2alg=aes256-sha1;modp1536 phase2=esp ike=aes256-sha1;modp1536
It's mirrored exactly the same on the other side.
I have tried changing the dead peer detection timeout to something high (5 minutes), and removing it completely (which I believe defaults it to 30 seconds), neither of which made any difference.
I can't see any very obvious errors in the logs, however the most recent drop out produced the following message around the same time:
Feb 10 00:53:09 site-b-vpn pluto[30584]: "site-a/5x5" #39: max number of retransmissions (2) reached STATE_QUICK_I1 Feb 10 00:53:09 site-b-vpn pluto[30584]: "site-a/5x5" #39: starting keying attempt 2 of an unlimited number Feb 10 00:53:09 site-b-vpn pluto[30584]: "site-a/5x5" #95: initiating Quick Mode PSK+ENCRYPT+TUNNEL+PFS+UP+IKEv2ALLOW+SAREFTRACK to replace #39 {using isakmp#52 msgid:119495de proposal=AES(12)_256-SHA1(2)_160 pfsgroup=OAKLEY_GROUP_MODP1536}
and also
Feb 10 00:52:25 site-a-vpn pluto[2414]: "site-b/6x6" #1: ignoring Delete SA payload: PROTO_IPSEC_ESP SA(0xde58eea3) not found (maybe expired) Feb 10 00:52:25 site-a-vpn pluto[2414]: "site-b/6x6" #1: received and ignored informational message Feb 10 00:52:25 site-a-vpn pluto[2414]: "site-b/6x6" #1: ignoring Delete SA payload: PROTO_IPSEC_ESP SA(0xa5298d7d) not found (maybe expired) Feb 10 00:52:25 site-a-vpn pluto[2414]: "site-b/6x6" #1: received and ignored informational message
Before we move to another solution, does anyone have any suggestions on what the problem might be? Running a constant ping between the two hosts doesn't drop *any* packets (even when the IPSec connection itself drops out).
Thanks in advance.