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Mavericks network issue

Since I upgraded my MBA late 2010 from 10.6 to Mavericks, random network "unreachable" happens now and then. When the "unreachable" happens, the WIFI keeps connected, but applications can't connect to outside (there are exceptions, see below). The only cure is turn WIFI off and on. The randomness is timing: you may use it w/o problem for hours, then you keeps encountering problem within minutes time frame after turning WIFI off and on.


At first, I think it is buggy WIFI driver or WIFI device incompatibility (though WIFI works without any problem before upgrade). I spent a lot of time to find the real reason, and now it seems that some OS mechanism kicks in when problem shows off.


I have MBA (192.168.0.100), a router box (192.168.0.254) and server box (192.168.0.250). Router box runs dns, ssh, nginx and acts as NAT gateway.

1. keep a 'ping 192.168.0.254' in MBA's terminal

2. keep ssh connection to 192.168.0.254 and 192.168.0.250 from MBA (maybe run 'top' or other program which output continuously)


I use firefox, chrome and safari to browse internet. When I see browser shows "looking up" or "connecting" but freezes there, one of the following is true:

1. ping shows "Request timeout for icmp_seq XXX"

2. ping shows "64 bytes from 192.168.0.254: icmp_seq=XXX ttl=64 time=??? ms"


Sometimes(i.e, not always), these are true:

1. both 'telnet 192.168.0.254 22' and 'telnet 192.168.0.250 22' can't connect

2. both ssh connections work fine: I can type and get feedback or watch 'top' running and refreshing in ssh session

3. I can log out both ssh connection and re-login without problem

4. dns queries freeze

5. 'ping 192.168.0.250' timeout

6. 'telnet 192.168.0.254 22', then run tcpdump on both MBA and router, I can see it's packets (syn packet) sent out in MBA's end but no packet received in router's end. The unusual thing is TCP retries never end

7. 'ping 192.168.0.100' from 192.168.0.254 works fine


PUT IT SIMPLE: when network is unreachable, sometimes existing tcp connections still work, and ping randomly works or not; no clues about why this happens.


And the firewall on MBA is always turned off.


After this OS upgrade, this MBA is very hard to use. I don't know OS X much, and usually this MBA is used by my wife and she just do some web surfing. I had to spend a lot of time to try to resolve this problem.


Any help is welcome. If any furthur information is needed, feel free to ask.


T.I.A

MacBook Air

Posted on Nov 17, 2013 8:53 AM

Reply
25 replies

Nov 17, 2013 11:40 AM in response to larkw

More details and clarification for 'ping 192.168.0.254 timeout' case:


1. When 'unreachable' happens, telnet can still connect 192.168.0.254, but wait for 30 sec dns timeout or connect immediately with 'telnet -N'

2. 'host some.domain.name' works, the dns server on 192.168.0.254 responses correctly

3. 'ping www.google.com' gives 'ping: cannot resolve www.google.com: Unknown host'. so it's MBA's local dns service/helper doesn't work

4. MBA's arp resolution doesn't work. If given enough time, the arp entry for 192.168.0.254 will expires and be removed, then ssh connection broken


So far, conclusion:

1. arp resolution stop working. this maybe WIFI related

2. icmp packets drop at MBA's end. this maybe WIFI related

3. local dns service/helper stop working


For 'network unreachable but ping 192.168.0.254 works' case, I think it is

1. arp resolution stop working. this maybe WIFI related

2. local dns service/helper stop working

Nov 19, 2013 8:41 AM in response to larkw

Same problem exactly. I thought it was my router so I bought a brand new Netgear R6250. Waste of money and the problem continues. Sometimes I can go an hour before I lose internet connectivity but often much less than that (minutes). Shows I'm still connected to the internal network, but I have to turn off/on the wifi connection to actually get online. Same issue connecting to my wifi printer. Sometimes I have to toggle my wifi connection just to print. Happens sporadically and frequently. My poor MBP has almost been thrown out the window a few times... it is ESENTIALLY unusable. This is a huge problem on my home network.


Another, possible related topic... when I connect to my small office network, my co-workers computers (Dell PC) internet connection slows to a crawl. I turn my wifi off... he can surf normally. I am out of the office, he surfs normally. Only when I am in the office is it crawling. Seems like this might be related. Oddly, I RARELY get dropped from my work network. The only problem I have on this network, is my co-workers PC. We have a Netgear WNR854T here. Both routers have the latest firmware.


Model Name: MacBook Pro

Model Identifier: MacBookPro10,2

Processor Name: Intel Core i5

Processor Speed: 2.6 GHz

Number of Processors: 1

Total Number of Cores: 2

L2 Cache (per Core): 256 KB

L3 Cache: 3 MB

Memory: 8 GB

Boot ROM Version: MBP102.0106.B03


System Version: OS X 10.9 (13A603)

Kernel Version: Darwin 13.0.0

Boot Volume: Macintosh HD

Boot Mode: Normal

Secure Virtual Memory: Enabled

Time since boot: 20 days 23:15


Firewall Settings:

Mode: Limit incoming connections to specific services and applications

Services:

File Sharing (AFP): Allow all connections

Printer Sharing: Allow all connections

Applications:

com.aliph.Jawbone_Updater: Allow all connections

com.apple.iTunes: Allow all connections

com.rogueamoeba.Airfoil: Allow all connections

com.spotify.client: Allow all connections

Firewall Logging: Yes

Stealth Mode: No


Interfaces:

en0:

Card Type: AirPort Extreme (0x14E4, 0x10F)

Firmware Version: Broadcom BCM43xx 1.0 (5.106.98.100.22)

MAC Address: 54:26:96:d6:c1:7d

Locale: FCC

Country Code: US

Supported PHY Modes: 802.11 a/b/g/n

Supported Channels: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 36, 40, 44, 48, 52, 56, 60, 64, 100, 104, 108, 112, 116, 120, 124, 128, 132, 136, 140, 149, 153, 157, 161, 165

Wake On Wireless: Supported

AirDrop: Supported

Status: Connected

Current Network Information:

mynetwork:

PHY Mode: 802.11n

BSSID: 00:1b:2f:d5:b2:62

Channel: 10

Country Code: US

Network Type: Infrastructure

Security: WPA2 Personal

Signal / Noise: -42 dBm / -88 dBm

Transmit Rate: 130

MCS Index: 15

Nov 20, 2013 7:28 AM in response to larkw

My system is also behaving like this. Are you using any VPN software? I use Juniper Network Connect to connect to my work VPN, and when I'm running that, then the problem appears just like what you describe.


Two other behaviors that might be related to this.


1) After the connection goes up and down for a while, I will eventually get "cannot allocate buffer" errors from ping. At that point I have to reboot Mac OS.


2) Since upgrading to Mavericks, I've had three kernel crashes. All of them have happened when the system is going to sleep, i.e., I notice the problem when I open the clamshell and see the login page rather than where I was before, and I get the message about reporting the crash dump to Apple.


There is a Cisco thread (https://supportforums.cisco.com/thread/2247235) about Any Connect (which I do not use) that talks about a Mavericks bug in the networking software (Apple Bug Report ID 15261749). However, I don't know how to see this report to see if there is any solution from Apple.

Nov 20, 2013 12:42 PM in response to larkw

Similar issue here as well. After upgrading 2010 Mac Pro to Mavericks from Snow Leopard.


My network connections drops randomly and is doesn't matter if I am wired or wireless. If I do nothing, I am unable to access internet, mail servers or networked drives and eventually my network drives are unmounted and the ethernet connection disconnects and sets itself to a self-assigned IP. It can take several minutes before a connection is reestablished.


I have reduced the disruption somewhat but am looking for a fix. Currenlty I have to keep wifi ON as well as connect with ethernet (Primary Service). If I catch it when it begins I can Renew DHCP Lease for my ethernet and then toggle wifi OFF then back ON. This reconnects me relatively instantly through my wifi while my ethernet reestablishes. It also stops my networked drives from unmounting.


I have tried the suggestions here: https://discussions.apple.com/thread/5537854?answerId=23720833022#23720833022 but none have worked. Any help is appreciated. I would love to avoid a clean reinstall.

Nov 24, 2013 5:39 AM in response to larkw

I have exactly the same issue. The wifi speed drops, and deactivating and reconnecting the wifi will increase the speed for little while until the speed drops once again. Its definitely the Macbook since the cable connection to the router with my PC and Wifi connection with another Windows Laptop are just fine.


Macbook Air 13 2013 Mavericks, no VPN running


So Apple please fix this!

Dec 9, 2013 5:06 PM in response to larkw

+1 to this issue. I didn't notice it until I upgarded my router to an 802.11ac router and run it in dual 5.8 and 2.4ghz mode.


The problem only happens on the 5.8ghz network, and switching to the 2.4ghz network "fixes" the issue. Other devices on the same 5.8ghz network don't have any issues (an xbox one stays connected 24/7 with no issues to the same network).


When it happens the wifi logo says it's connected, but pinging the gateway (192.168.0.1) results in no route to host.


I also disabled the "ac" network mode and set it to only 802.11n, but the problem persists.


Edit: Also using WPA2+PSK security on both 5.8 and 2.4ghz networks.

Dec 9, 2013 5:11 PM in response to Geoff Stearns

Here's a Wifi info dump when my network just disconnected:


"Old Custer" is the problem network, 111 Archer Avenue is my 2.4ghz network that still works fine.


Hope this helps.

Software Versions:

CoreWLAN: 4.0 (400.45.1)

CoreWLANKit: 3.0 (300.35)

Menu Extra: 9.0 (900.34)

System Information: 9.0 (900.8)

IO80211 Family: 6.0 (600.34)

Diagnostics: 3.0 (300.37)

AirPort Utility: 6.3.2 (632.3)

Interfaces:

en0:

Card Type: AirPort Extreme (0x14E4, 0xE9)

Firmware Version: Broadcom BCM43xx 1.0 (5.106.98.100.22)

MAC Address: 28:37:37:21:08:8a

Locale: FCC

Country Code: US

Supported PHY Modes: 802.11 a/b/g/n

Supported Channels: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 36, 40, 44, 48, 52, 56, 60, 64, 100, 104, 108, 112, 116, 120, 124, 128, 132, 136, 140, 149, 153, 157, 161, 165

Wake On Wireless: Supported

AirDrop: Supported

Status: Connected

Current Network Information:

Old Custer:

PHY Mode: 802.11n

BSSID: 64:66:b3:a4:25:b2

Channel: 161,-1

Country Code: US

Network Type: Infrastructure

Security: WPA2 Personal

Signal / Noise: -76 dBm / -87 dBm

Transmit Rate: 108

MCS Index: 11

Other Local Wi-Fi Networks:

111 Archer Ave:

PHY Mode: 802.11n

BSSID: 64:66:b3:a4:25:b3

Channel: 9,-1

Network Type: Infrastructure

Security: WPA/WPA2 Personal

Signal / Noise: -61 dBm / -92 dBm

3ZWP2:

PHY Mode: 802.11n

BSSID: 00:26:b8:45:b5:34

Channel: 6

Country Code: US

Network Type: Infrastructure

Security: WEP

Signal / Noise: -84 dBm / -92 dBm

5RG6Q:

PHY Mode: 802.11n

BSSID: f8:e4:fb:d9:7f:39

Channel: 1

Network Type: Infrastructure

Security: WPA2 Personal

Signal / Noise: -85 dBm / -92 dBm

DG860A02:

PHY Mode: 802.11n

BSSID: 5c:57:1a:bc:65:00

Channel: 1

Country Code: US

Network Type: Infrastructure

Security: WPA/WPA2 Personal

Signal / Noise: -83 dBm / -92 dBm

Go, Mordecai!:

PHY Mode: 802.11n

BSSID: 62:66:b3:a4:25:b3

Channel: 9,-1

Network Type: Infrastructure

Security: None

Signal / Noise: -64 dBm / -92 dBm

Jonathan’s MacBook Pro:

PHY Mode: 802.11g

BSSID: 68:a8:6d:30:02:12

Channel: 11

Network Type: Infrastructure

Security: WEP

Signal / Noise: -82 dBm / -92 dBm

KY7TB:

PHY Mode: 802.11n

BSSID: 00:7f:28:5e:f9:49

Channel: 6

Country Code: US

Network Type: Infrastructure

Security: WPA2 Personal

Signal / Noise: -83 dBm / -92 dBm

M68O0:

PHY Mode: 802.11n

BSSID: 00:26:b8:11:3f:73

Channel: 6

Country Code: US

Network Type: Infrastructure

Security: WEP

Signal / Noise: -83 dBm / -92 dBm

MKLQN:

PHY Mode: 802.11n

BSSID: 00:7f:28:c9:ea:6d

Channel: 6

Country Code: US

Network Type: Infrastructure

Security: WPA2 Personal

Signal / Noise: -68 dBm / -92 dBm

SavageInc:

PHY Mode: 802.11n

BSSID: 84:1b:5e:36:55:d7

Channel: 11

Network Type: Infrastructure

Security: WPA2 Personal

Signal / Noise: -84 dBm / -92 dBm

belkin.2c9:

PHY Mode: 802.11n

BSSID: ec:1a:59:ad:42:c9

Channel: 1

Network Type: Infrastructure

Security: WPA2 Personal

Signal / Noise: -72 dBm / -92 dBm

belkin.7a0:

PHY Mode: 802.11n

BSSID: 08:86:3b:fb:07:a0

Channel: 11

Network Type: Infrastructure

Security: WPA2 Personal

Signal / Noise: -60 dBm / -92 dBm



Geoff Stearns wrote:


+1 to this issue. I didn't notice it until I upgarded my router to an 802.11ac router and run it in dual 5.8 and 2.4ghz mode.


The problem only happens on the 5.8ghz network, and switching to the 2.4ghz network "fixes" the issue. Other devices on the same 5.8ghz network don't have any issues (an xbox one stays connected 24/7 with no issues to the same network).


When it happens the wifi logo says it's connected, but pinging the gateway (192.168.0.1) results in no route to host.


I also disabled the "ac" network mode and set it to only 802.11n, but the problem persists.


Edit: Also using WPA2+PSK security on both 5.8 and 2.4ghz networks.

Dec 19, 2013 6:57 AM in response to Magnetics

Magnetics wrote:


@etresoft - How can you say it has nothing to do with Mavericks (or either of the Lions) since a number of us did not have network issues prior to upgrading from Snow Leopard?

Because this is a yearly ritual now that Apple is going to yearly OS releases. ISPs hand out cheap routers that are tested only with Windows and whatever OS Apple was using 3 years ago. Ergo, if you use that router with a 3 year-old OS, you will get good results.

Dec 19, 2013 7:42 AM in response to etresoft

etresoft wrote:


Magnetics wrote:


@etresoft - How can you say it has nothing to do with Mavericks (or either of the Lions) since a number of us did not have network issues prior to upgrading from Snow Leopard?

Because this is a yearly ritual now that Apple is going to yearly OS releases. ISPs hand out cheap routers that are tested only with Windows and whatever OS Apple was using 3 years ago. Ergo, if you use that router with a 3 year-old OS, you will get good results.

Well, All I can say is that I'm experiencing this issue when I am connected by ethernet to our LAN server box (Windows) or through the wireless router. All software/firmware is up to date for all devices and yet the problem persists. And since the the networking utilities in Mavericks are supposedly the same as the 2+ year old Lion OS, I would have to believe that the updates would have addressed this issue already.


For me at least, this is not just an internet or wifi issue. All network activity slows (Local or otherwise), hangs and then disconnects. Your advice to check out hardware/software outside of our computers is good advice. However, it is something I have done and do regularly and nothing has solved the issue.

Mavericks network issue

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