On 9/15/18 3:44 AM, Alex wrote:
On Fri, Sep 14, 2018 at 4:24 PM Daniel J. Luke <dl...@geeklair.net> wrote:
On Sep 14, 2018, at 3:26 PM, Kevin A. McGrail <kmcgr...@apache.org> wrote:
On 9/14/2018 3:22 PM, Alex wrote:
I wish it were that easy. /etc/resolv.conf is set up to use 127.0.0.1,
which is bind configured as a my local caching resolver.
Sinister issues like this are hard. I'll try and escalate our plans for
rsync access.
Alex - have you looked at bad checksum counters on the host? (netstat -s) -
I've seen strange issues before with broken network hardware (or bugs in
switch/router code) caused changes to packets as they passed through the 'bad'
device. The first hints were those counters increasing at the same time as the
mysterious issue happening.
I don't see anything relating to bad checksums with netstat :-( I've
also tried numerous ethtool config changes. I've also looked through
hundreds of packets with tcpdump and wireshark.
This isn't a spamassassin message, but does anyone with a postfix
system ever see similar "Name service error" messages such as the one
below?
Sep 14 21:12:54 mail03 postfix/dnsblog[3713]: warning: dnsblog_query:
lookup error for DNS query 239.242.238.54.ubl.unsubscore.com: Host or
domain name not found. Name service error for
name=239.242.238.54.ubl.unsubscore.com type=A: Host not found, try
again
It appears to occur quite frequently, and on multiple unrelated
systems. I'd love to find out what's causing it. The postfix people
ascribed it to a remote server problem, but I can't believe virtually
all RBLs, including spamhaus, would have such intermittent problems
with *their* name servers.
Maybe something in your setup is throttling UDP traffic.
I've seen Zyxel DSL modems do this.
Some new IDS in your firewall?
