DNS issues after 10.6.5 update

In my case I'm always using the computer when the problem happens... suddenly hostnames stop being resolved. So I don't think it's a sleep issue for me. I've also been unable to reset mDNSResponder by either resetting the network connection or changing the network connect. Once mDNSResponder craps out turning the airport off/on or switch from wireless to wired has no affect.

Hmm, it seems I have exactly the same problem. I have a late 2007 white MacBook. The problem usually happens while I am working, both when I use a wireless or a wired connection. Very annoying that I have to reboot to solve the issue...

Thanks for the tip on changing CNAMEs to A records! This works!!

It would seem that for some reason Mac os X 10.6.5 will not accept domain aliases that resolve to out of zone.

I guess this makes sense given the number of DNS intercepting viruses/trojans etc that are out there on PCs - maybe Apple are pre-empting something!

I got the same problem.
I updated to 10.6.5 and some sites just cannot be loaded.

May be there is something wrong with 10.6.5 update, related to DNS issues...

http://discussions.apple.com/thread.jspa?messageID=12617327

I changed DNS setting using Google Public DNS service,
and everything is OK now.

http://code.google.com/speed/public-dns/
Hope this helps.

hungnv wrote:
I changed DNS setting using Google Public DNS service,
and everything is OK now.

Note that if you switch to Google Public DNS or OpenDNS and your resolution works, the problem is with your previous DNS servers, not with Mac OS X.

Same problem 4-5 times a day. Here is a photo of the tail end of the shutdown sequence that I see (verbose mode) every time I restart to clear the problem. http://bit.ly/dQQGGN

Its driving me MAD!

I can reproduce this on my MacBook Pro since weeks now!!

Is Apple the new Microsoft?

So it appears that nobody has solved the problem as of yet.

The one thing to add is that this seems to have something to do
with /usr/sbin/awascd. I don't really know what this process is for
but it appears to have something to do with name lookups via standard
gethostbyaddr etc.

Currently I see 2 situations: first name lookup completely hang and the calling
process is stuck i.e. ping foo.example.com.
second name lookup fail with a host not found message.
But the whole time nslookup / host / dig works just fine, so it's not an issue of talking
to the DNS server.

awacsd seems to be something new in 10.6.5 since I don't find it on my 10.6.4 system (which is working just fine).

Anybody know how to debug awascd

-Russell

Hi 🙂

http://discussions.apple.com/thread.jspa?threadID=2643968&tstart=0 quotes the man page for awascd
is an executable invoked by launchd to facilitate connections
between devices using Back to My Mac...

I've been hit with this problem, and I think I can see what's going wrong.

I have an internal Active Directory domain which is used for DNS, which is on a .local (we'll call it mydomain.local)
We also have another domain (we'll call it otherdomain.com) which is used for externally accessable resources, we have an internal DNS server with otherdomain.com as an ctive zone with CNAME records pointing to .mydomain.local hosts.

This is a common setup, I work with a lot of businesses and this is a very standard way to do things, so you can give users 1 hostname for access to a service and internally it points to the internal IP and externally it points to your forwarded external IP.

OK, enough history.

I put mDNSResponder into debug mode as per it's man page entry

I then 'pinged' an otherdomain.com address which resolves as a CNAME to a mydomain.local address

Here is the logs:

Thu Nov 25 11:42:36 smlt8001 mDNSResponder[31] <Warning>: 14: DNSServiceCreateConnection START
Thu Nov 25 11:42:36 smlt8001 mDNSResponder[31] <Warning>: 14: Error socket 31 created 00000000 00000001
Thu Nov 25 11:42:36 smlt8001 mDNSResponder[31] <Warning>: 14: DNSServiceQueryRecord(5000, 0, mx2.otherdomain.com., Addr) START
Thu Nov 25 11:42:36 smlt8001 mDNSResponder[31] <Info>: GetServerForQuestion: 0000000101006C88 DNS server 192.168.2.222:53 (Penalty Time Left 0) (Scope None:0000000000000000) found for name mx2.otherdomain.com. (Addr)
Thu Nov 25 11:42:36 smlt8001 mDNSResponder[31] <Info>: mDNS StartQueryinternal: question 0000000101006C88 mx2.otherdomain.com. (Addr), DNS Server 192.168.2.222:53
Thu Nov 25 11:42:36 smlt8001 mDNSResponder[31] <Warning>: 14: Error socket 31 closed 00000000 00000001 (0)
Thu Nov 25 11:42:36 smlt8001 mDNSResponder[31] <Warning>: 14: DNSServiceQueryRecord(mx2.otherdomain.com., Addr) ADD 23 mx2.otherdomain.com. CNAME app2.mydomain.local.
Thu Nov 25 11:42:36 smlt8001 mDNSResponder[31] <Info>: AnswerCurrentQuestionWithResourceRecord: 0000000101006C88 mx2.otherdomain.com. (Addr) following CNAME referral 0 for 23 mx2.otherdomain.com. CNAME app2.mydomain.local.
Thu Nov 25 11:43:06 smlt8001 mDNSResponder[31] <Warning>: 14: Cancel 00000000 00000001
Thu Nov 25 11:43:06 smlt8001 mDNSResponder[31] <Warning>: 14: DNSServiceQueryRecord(app2.mydomain.local., Addr) STOP
Thu Nov 25 11:43:06 smlt8001 mDNSResponder[31] <Warning>: 14: Error socket 31 created 00000000 00000002
Thu Nov 25 11:43:06 smlt8001 mDNSResponder[31] <Warning>: 14: DNSServiceQueryRecord(5000, 0, mx2.otherdomain.com.mydomain.local., Addr) START
Thu Nov 25 11:43:06 smlt8001 mDNSResponder[31] <Warning>: 14: DNSServiceQueryRecord(mx2.otherdomain.com.mydomain.local., Addr) unicast
Thu Nov 25 11:43:06 smlt8001 mDNSResponder[31] <Info>: GetServerForQuestion: 0000000100837D78 DNS server 192.168.2.222:53 (Penalty Time Left 0) (Scope None:0000000000000000) found for name mx2.otherdomain.com.mydomain.local. (Addr)
Thu Nov 25 11:43:06 smlt8001 mDNSResponder[31] <Info>: mDNS StartQueryinternal: question 0000000100837D78 mx2.otherdomain.com.mydomain.local. (Addr), DNS Server 192.168.2.222:53
Thu Nov 25 11:43:06 smlt8001 mDNSResponder[31] <Warning>: 14: Error socket 31 closed 00000000 00000002 (0)
Thu Nov 25 11:43:06 smlt8001 mDNSResponder[31] <Info>: mDNSCoreReceiveResponse ignoring 58 mydomain.local. SOA dc.mydomain.local. hostmaster. 47683 900 600 86400 900
Thu Nov 25 11:43:06 smlt8001 mDNSResponder[31] <Info>: Skipping check to see if we need to generate a negative cache entry for mx2.otherdomain.com.mydomain.local. (Addr)
Thu Nov 25 11:43:07 smlt8001 mDNSResponder[31] <Info>: mDNSCoreReceiveResponse ignoring 58 mydomain.local. SOA dc.mydomain.local. hostmaster. 47683 900 600 86400 900
Thu Nov 25 11:43:07 smlt8001 mDNSResponder[31] <Info>: Skipping check to see if we need to generate a negative cache entry for mx2.otherdomain.com.mydomain.local. (Addr)
Thu Nov 25 11:43:08 smlt8001 mDNSResponder[31] <Warning>: 14: Cancel 00000000 00000002
Thu Nov 25 11:43:08 smlt8001 mDNSResponder[31] <Warning>: 14: DNSServiceQueryRecord(mx2.otherdomain.com.mydomain.local., Addr) STOP
Thu Nov 25 11:43:08 smlt8001 mDNSResponder[31] <Warning>: 14: DNSServiceCreateConnection STOP

This is messed up.

It's looking up mx2.otherdomain.com and getting a CNAME of app2.mydomain.local.
It's then trying to look up mx2.otherdomain.com.mydomain.local

Why?

At first I thought it was not handling the '.' on the end of the CNAME and treating it as a relative name rather than a FQDN, but that's not it, because that would resolve to app2.mydomain.local.otherdomain.com NOT mx2.otherdomain.com.mydomain.local

Something is seriously hosed in the part of mDNSResponder in 10.6.5 when it handles a CNAME to a .local domain

Steven

Message was edited by: SBlackery

I have same problems since update to 10.6.5.
Process of mDNSresponder was crashed and reported about crashreport at /Library/Logs/CrashReporter.

List on CrashReport:
------
admin-no-macbook:log root# cd /Library/Logs/CrashReporter/
admin-no-macbook:CrashReporter root# ls
mDNSResponder 2010-11-14-235729localhost.crash
mDNSResponder 2010-11-17-142126localhost.crash
mDNSResponder 2010-11-18-090429localhost.crash
mDNSResponder 2010-11-18-125943localhost.crash
mDNSResponder 2010-11-18-210321localhost.crash
mDNSResponder 2010-11-20-133039localhost.crash
mDNSResponder 2010-11-22-071250localhost.crash
mDNSResponder 2010-11-23-084515localhost.crash
mDNSResponder 2010-11-24-120604localhost.crash
mDNSResponder 2010-11-25-193637localhost.crash
admin-no-macbook:CrashReporter root#

------

When crash process of mDNSResponder, segfault the process and record system.log:
Nov 25 19:36:28 admin-no-macbook mDNSResponder[4570]: * process 4570 exceeded 500 log message per second limit - remaining messages this second discarded *
Nov 25 19:36:30 admin-no-macbook mDNSResponder[4570]: * process 4570 exceeded 500 log message per second limit - remaining messages this second discarded *
Nov 25 19:36:31 admin-no-macbook mDNSResponder[4570]: * process 4570 exceeded 500 log message per second limit - remaining messages this second discarded *
Nov 25 19:36:36 admin-no-macbook com.apple.launchd[1] (com.apple.mDNSResponder[4570]): Job appears to have crashed: Segmentation fault
Nov 25 19:36:37 admin-no-macbook com.apple.ReportCrash.Root[6323]: 2010-11-25 19:36:37.721 ReportCrash[6323:2a03] Saved crash report for mDNSResponder[4570] version ??? (???) to /Library/Logs/DiagnosticReports/mDNSResponder 2010-11-25-193637localhost.crash

Under happens crashing process of mDNSResponder, I still can execute that:
- ping defaultgateway and DNS server, by IP Address.
- lookup hosts by nslookup (eg www.google.com, www.apple.com )
- host command (eg host admin-no-macbook.local has address 192.168.3.100)
But I cannot execute that.
- cannot browse internet (Firefox, Safari ...)
- "telnet www.google.com 80" is not responsed. (nodename nor servname provided, or not known)
- opening system Preference - share is not responsed.

I hove nothing solved this problem, too.

This works for me. When DNS craps out on OSX, I switch over to XP (under Parallels Desktop, but it will probably work the same under Fusion) and if I select the Default Adapter for Bridged Networking in Parallels Prefs then DNS still works in all the XP web browsers. It's not exactly an ideal solution, but it's not that bad either because it turns out that Firefox on XP is much faster than on OSX. Firefox has become a real dog on OSX.

It sounds like no one has yet resolved the full DNS failure problem. It also sounds like no one has worked out a way to restart mDNSResponder when it hangs. For those folks who have this problem (as opposed to the CNAME issue), have you tried reinstalling the OS? At this point I can't work out any other options.