For quite some time, I’ve had a strange problem with an iMac waking up from sleep. The network connection does not work for anything from 30s to 2 minutes, and then the problem just vanishes and it works at full speed (100mbit fiber). This problem only affects the mac, I have Linux and Windows machines + mobile devices working as expected.
After fighting everything I could in the OS and even doing a clean install of the operating system I started to eliminate all other devices from the network. I just down all wireless AP’s, bypassed the switch the computer is connected to and even changed all the cables but nothing helped. Finally I just connected the computer directly to the internet and it works as expected, network is up within seconds of wake up.
I tested two other routers (Linksys with Apple Airport Extreme) with default settings and they work without any problems, next I reset the Mikrotik to default settings and even upgraded to last v5 packages and now 6.1 and the problem persists…
Does anyone have a clue what could be causing this? I tried sniffing packages on the router while the machine is waking up, and it seemed to be repeating itself as if the responses never came back (I can see the router did respond to everything). I set mDNSResponder (on the mac) loglevel to debug and it is a big mess.
(cleaned)
DNSServiceQueryRecord(www.google.com., Addr) ADD 0 www.google.com. Addr
Cancel 00000000 00000759
DNSServiceQueryRecord(www.google.com., Addr) STOP PID[394](Google Chrome)
Cancel 00000000 00000059
Error socket 29 created 00000000 0000075A
RetryQuestionWithSearchDomains(kpucsazbci., Addr), retrying after appending search domain
...
network changed: v4(en0+:192.168.88.254) DNS+ Proxy+ SMB
...
SendQueries putting 24 . OPT Max 1440 Vers 0 Seq 9 MAC 00:25:00:D4:D4:CC I-MAC 00:1C:42:00:00:08
...
DNSServiceBrowse(_adisk._tcp.local., PTR) RESULT Add 4: 31 _adisk._tcp.local. PTR DiskStation._adisk._tcp.local.
DNSServiceBrowse(_afpovertcp._tcp.local., PTR) RESULT Add 4: 36 _afpovertcp._tcp.local. PTR DiskStation._afpovertcp._tcp.local.
Error socket 84 created 00000000 0000000F
DNSServiceQueryRecord(4100, 4, DiskStation._device-info._tcp.local., TXT) START PID[318](NetworkBrowserA)
Error socket 84 closed 00000000 0000000F (0)
....
On the routerboard end it seems like it is responding, but here it’s just repeating everything like it was never sent.
The strange thing is, that anything apart from the mikrotik router just works.