[exim] DKIM behavior change following a reboot

Hi,

After some troubleshooting advice, hope someone has seen this before!

We have Exim 4.71 on a Ubuntu 10.04 server that we use for shared hosting accounts. We rebooted all the servers in this system a few weeks ago, and since then the email server seems to be having a problem verifying DKIM for any email from Google's systems (googlemail.com, gmail.com etc.)

2012-09-22 10:30:00 1TFM2C-0001EU-JU DKIM: d=gmail.com s=20120113 c=relaxed/relaxed a=rsa-sha256 [verification succeeded]
2012-09-22 10:34:03 1TFM67-0001Je-4i DKIM: d=gmail.com s=20120113 c=relaxed/relaxed a=rsa-sha256 [verification succeeded]
2012-09-22 11:34:05 1TFN29-0003HJ-LG DKIM: d=gmail.com s=20120113 c=relaxed/relaxed a=rsa-sha256 [verification succeeded]
2012-09-22 12:14:10 1TFNel-0003oJ-Dt DKIM: d=gmail.com s=20120113 c=relaxed/relaxed a=rsa-sha256 [verification succeeded]
2012-09-22 12:28:14 1TFNsU-0004YD-0H DKIM: d=gmail.com s=20120113 c=relaxed/relaxed a=rsa-sha256 [verification succeeded]
2012-09-22 16:24:59 1TFQqK-0000w5-Om DKIM: d=gmail.com s=20120113 c=relaxed/relaxed a=rsa-sha256 [invalid - public key record (currently?) unavailable]
2012-09-22 16:34:35 1TFQzS-0001rY-Mf DKIM: d=gmail.com s=20120113 c=relaxed/relaxed a=rsa-sha256 [invalid - public key record (currently?) unavailable]
2012-09-22 16:35:56 1TFR0v-0001v9-B4 DKIM: d=gmail.com s=20120113 c=relaxed/relaxed a=rsa-sha256 [invalid - public key record (currently?) unavailable]
2012-09-22 16:47:51 1TFRCS-0002OL-7P DKIM: d=gmail.com s=20120113 c=relaxed/relaxed a=rsa-sha256 [invalid - public key record (currently?) unavailable]

Users on this system have noticed that emails from Gmail are repeatedly being delivered locally (remote id is the same each time). Can anyone explain why this is happening? Our support guys have spent some hours checking but there is very little information about this particular error. It worked fine before the reboot, and no config changes have been made to Exim.

2012-10-01 22:47:57 1TInAm-0004OA-Vw <= x@??? H=mail-vb0-f54.google.com [209.85.212.54] P=esmtp S=4408 id=CAHUGyMEOGCrDjak+O5whM3VU63FNUfiBVWko9PCM5AmUht+5Bg@???
2012-10-01 23:05:03 1TInRV-0004oi-Se <= x@??? H=mail-vb0-f54.google.com [209.85.212.54] P=esmtp S=4408 id=CAHUGyMEOGCrDjak+O5whM3VU63FNUfiBVWko9PCM5AmUht+5Bg@???
2012-10-01 23:43:14 1TInyI-00070X-Ja <= x@??? H=mail-vc0-f182.google.com [209.85.220.182] P=esmtp S=4472 id=CAHUGyMEOGCrDjak+O5whM3VU63FNUfiBVWko9PCM5AmUht+5Bg@???
2012-10-02 00:26:03 1TIodZ-00006T-Cv <= x@??? H=mail-vc0-f182.google.com [209.85.220.182] P=esmtp S=4528 id=CAHUGyMEOGCrDjak+O5whM3VU63FNUfiBVWko9PCM5AmUht+5Bg@???




Best Wishes,
Michelle Pooley

Technical Manager

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Tel: 0800 1 777 000
http://www.cwcs.co.uk

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