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Tracking down Peter's lockout

I've been driven bananas long enough by this problem. I have an entire evening with no interruptions (of course, also no sleep!) so I'm going to use the time to figure out WHERE on earth these lockouts are coming from.

We are gathering info from:
1. The ADLockout tool that monitors his logon status from both DCs. It is used to unlock his account as well.
2. A full netlogon log (all options selected) pulled from the ADLockout tool from DC-1.
3. Other methods I'm sure will be used.

By this point, we've deduced:
1. It's coming from ISA (Transitive Network logon of orthotic\peter from ISA2006 (via ISA2006))
2. It's not a bad password on a mapped share, or him typing them in incorrectly.
3. His saved cached of passwords in XP is clear.
4. He is having the problem regardless of the state of his laptop or desktop (e.g. if both are off, lockouts continue).
5. He has checked to see if his credentials were still in use for a VPN session he helped someone set up - the computer was off for days at a time and he was still getting locked out.
6. I have disabled his account and still the lockouts continue (although this may be normal behaviour).
7. This is now the second occurrance of this - it happened for a period of a week where I updated all anti-virus software, cleaned up the computer, etc etc etc, then promptly disappeared for a month.
8. It should also be noted that there are no entries at all from any computer other than ISA.
9. He is not attempting to VPN in with bad credentials - this is happening as I type this at 2:30am.
10. Not sure if this is relevant, but I seem to see all bad password counts from the main DC, and other times all from the secondary DC. Must just be a round-robin thing.
11. ISA has been rebooted several times, so that won't fix it.
10. It is completely capable of driving me insane. Him moreso.

Here's a sample of the netlogon log: (I used: findstr /I "peter" c:\netlogon.log > c:\peter.txt)

06/10 20:20:59 [LOGON] ORTHOTIC: SamLogon: Transitive Network logon of orthotic\peter from ISA2006 (via ISA2006) Entered
06/10 20:20:59 [LOGON] ORTHOTIC: SamLogon: Transitive Network logon of orthotic\peter from ISA2006 (via ISA2006) Returns 0xC000006A
06/10 20:21:00 [LOGON] ORTHOTIC: SamLogon: Transitive Network logon of orthotic\peter from ISA2006 (via ISA2006) Entered
06/10 20:21:00 [LOGON] ORTHOTIC: SamLogon: Transitive Network logon of orthotic\peter from ISA2006 (via ISA2006) Returns 0xC000006A
06/10 20:21:05 [LOGON] ORTHOTIC: SamLogon: Transitive Network logon of orthotic\peter from ISA2006 (via ISA2006) Entered
06/10 20:21:05 [LOGON] ORTHOTIC: SamLogon: Transitive Network logon of orthotic\peter from ISA2006 (via ISA2006) Returns 0xC0000234

Thanks to here: (http://support.microsoft.com/kb/189541), we know that a 6A return is 'bad password', and a 234 return is 'account locked out'.

We can watch my fruitless attempts to keep him not-locked out all day. And week. Things have been too busy to track this down.


At any rate, I am going to check ISA's logs now, and see if I can turn anything up.

ISA has many logs, some useful, some not so useful.

To find out who is failing VPN login sessions (because RRAS logs do not show this), check for: "C:\Program Files\Microsoft ISA Server\ISASummaries", and edit the latest summary file. It's gibberish, but it gives you two great pieces of the puzzle: usernames, and IP addresses. Sadly, it's just that - gibberish, and if you use the reports function in ISA to decode them, you lose all username and IP info. Lame.

I then figured, hey, if the IP keeps showing up, must be the source, right? Not so much...the report is a garbled mess.

I'm now down to refreshing the ADLockout tool every 10 seconds, and watching a packet capture on the WAN port filtering on port 1723 (pptp). 5 lockouts in an instant...no packets.

Argh.

More searching has revealed something interesting - a whole ton of [TCP segment of a reassembled PDU] from this IP: 121.235.177.227, supposedly registered in Beijing, China. Seems that someone in China likes our shoes, or is downloading the whole website.

There doesn't seem to be any way to glean the info I need...I think I'll need to look into expanding the logging that's actually ON ISA2006, and get sysinternals into the mix. That's a Monday job though. Thankfully I have tomorrow off.

Monday report:
His account is not locked after 4 days! Wonders! It was still locking on Thursday when I left.
We'll have to wait until next time this happens.

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