Apple Script provides a good solution:
tell application "System Events"
tell current location of network preferences
set myConnection to the service "VPN University"
if myConnection is not null then
if current configuration of myConnection is not connected then
You can use Network Link Conditioner.
You will want to ignore the testing settings. Make a Custom Profile and set to have no packets dropped and no delay. Start with uplink and downlink at 2.45 Mbps each and see if you need lower limits to prevent disconnects.
It is a free download in Xcode (go to Xcode → Open Developer Tool → More Developer Tools… and ...
OS X 10.9 and earlier provide ipfw and it allows you to define custom firewall rules. Create a pipe with limited bandwidth using ipfw and you can run your tests and simulations.
Create a pipe "1" limited to 500KBytes/s via
sudo ipfw pipe 1 config bw 500KByte/s
Guide all network traffic of port 80 through pipe "1" using
sudo ipfw add 1 pipe 1 src-port 80
You can try arp on the command-line:
arp -- address resolution display and control
The arp utility displays and modifies the Internet-to-Ethernet address translation tables used by the address resolution protocol (arp(4)). With no flags, the program displays the current ARP entry for hostname. The host may be specified by ...
Yes, those details are safe to provide. They are measurements of the quality of your wireless signal, and they contain no personal information.
You can view these and other details from the Wi-Fi icon in the menu bar. The trick is to press and hold the option key while you click on the icon (i.e. make sure you’re pressing the option key first before ...
You need to make specific network configuration:
System Preferences > Network > Location: > Edit Locations...
left down + button,
enter a new netowrk configuration name, for example Office / Wi-Fi + proxy,
choose it and configure it with the proxy setting you need.
You will have to make 2 network configurations one to go through your proxy, and ...
When your connections starts timing out, can you do arp -an in Terminal.app and see if you still have all MAC addresses in the ARP table? as in - your router's MAC address, or the host you're trying to ping?
If you do (and you have the time before it starts working again), can you flush the arp table (sudo arp -ad) and then see if your router's MAC address ...
It’s perfectly normal, and there’s no need to do anything (except click on OK to close the window) or worry about it. Safari is just showing you the encryption details for the apple.com website — you may have accidentally clicked on the green padlock.
InternetSharing does log which address gets a DHCP lease within:
Technically it is the bootpd daemon which does take care of this part of the network access.
You can track who is getting access to your network now with this command:
tail -f /var/log/system.log | grep 'bootpd.*\[en.\]'
and for Mavericks, Yosemite & El Capitan:
As we have found the solution using Comments, here's the formal response.
Whenever you experience issues with Safari, App Store, iTunes and any other service that uses the "same" WebKit, but seem to see no problem in Google Chrome or Firefox, it's good to check if you have your Proxies configuration clear. Since sometimes Chrome (and Firefox) override these ...
To add to the accepted answer: it looks like you shouldn't need XCode, just an account at the Apple Developer website (simpler than first downloading the 2GB XCode package if you don't have it already).
Go to https://developer.apple.com/downloads and search for "Network Link Conditioner" or "Additional Tools for XCode", the latter being the name of the ...
Terminal does not use proxy settings configured in the network preferences pane because it doesn't do any connection. Terminal just let you fire commands which will use the network in different ways.
When setting your http_proxy and https_proxy environment variables should not include the http: or https: prefixes.
Therefore the environment variable in your ...
You can do this using Parental Controls on the Guest account. See Apple's KB article regarding this for the procedure:
OS X Mountain Lion: Filter inappropriate Internet content
Manage a user with parental controls
Choose Apple menu > System Preferences, and then click Parental Controls.
Click the lock if it’s not unlocked, and enter an ...
This is going to be a starting point answer, hopefully you can find something strange while comparing the shots and fix the problem.
If you can connect to Skype that means you have connectivity, but your computer is unable to perform name resolution (that is, convert the address of a service -like a webpage- to an ip address). Skype may work because it ...
You can use a 3rd party app called Little Snitch to block Internet access for individual apps. Little Snitch comes with a limited 30 days free trial and costs € 45 for single user license thereafter.
Another alternative is Radio Silence, a network monitor and firewall app for macOS. It lets you control Internet access on an individual app basis. Radio ...
In my case this was caused by the Juniper/Pulse Secure VPN client's kernel extension, which was active even when not connected to the VPN. Unloading the kernel extension restored speed without a reboot.
Short term fix is to unload the extension, command copied from linked kb article:
sudo kextunload /Library/Extensions/PulseSecureFirewall.kext
Long term ...
Mac OS X 10.10+ users need to use dnctl and pfctl but documented usage examples aren't easy to find.
# Configure `pfctl` to use `customRule`.
(cat /etc/pf.conf && echo "dummynet-anchor \"customRule\"" && echo "anchor \"customRule\"") | sudo pfctl -f -
# Define `customRule` to pipe traffic to `pipe 1`.
# Note this is the actual port ...
You need to get more information, so please do some troubleshooting and report back.
Hold down the Option key while clicking on the Wi-Fi icon in the menu bar and let us know what you see. Lion: New Wi-Fi Diagnostics tool
When you first see the exclamation point appear, open
System Preferences > Network. If you get a window like ...
> lsof -i :58199
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
Transmiss 304 Fyodor 8u IPv4 0x2fbc34fe135e3895 0t0 UDP *:58199
lsof = list open files. See manual for more details.
You can see with "ps -ef" more info about the PID "lsof" gave you.
Open Keychain Access.
Make sure "login" is selected in the upper left under "Keychains" and manually delete every entry that is associated with Google (any entry with Google in the name, I deleted). Specifically, the entry "com.apple.account.Google.oauth-token" is the one to delete.
Go back to Internet Accounts and add your Google account.
You can try nettop(1) in the Terminal. It is pre-installed, and refreshes every few seconds to provide a dashboard of all open network connections with their usage. Better than lsof since it shows the usage data too.
Then hit 'd' and look for odd-looking entries or entries with consistently large traffic in the 'bytes in' or 'bytes out' column. ...
From the "Apple Watch User Guide"
Apple Watch uses Bluetooth® wireless technology to connect to its paired iPhone and uses the iPhone for many wireless functions. Apple Watch can’t configure new Wi-Fi networks on its own, but it can connect to Wi-Fi networks you’ve set up on the paired iPhone.
If your Apple Watch and iPhone are on the same network ...
You can suspend and then kill the ssh process that's hung up. To do this you have to issue the escape sequence, suspend the ssh process, and then use kill -9 to kill that process.
The default escape key for the ssh that ships with OS X the ~ character. You have to enter it immediately after a new line for ssh to respect it. And then the key sequence Control-...
I've successfully solved this twice already using the following method:
In the Terminal.app (/Applications/Utilites/Terminal.app) type...
sudo ifconfig en1 down
sudo ifconfig en1 up
Which is surprising, because I thought that this is just the same as turning the Airport off and back on - which I've tried before, but did not succeed.
However, maybe that's ...
If your iOS device is on version 5.0 or higher, then yes, you can do it directly from the handset by going to Settings/General/Software Update.
If you're on iOS 4.x then no, you will need a computer to do this.
To upgrade in your situation, I would recommend the following steps:
1) On your new laptop, open iTunes, and in the preferences on the devices tab, ...
In agreement with the original poster, in this answer I put together the comments above that describe the troubleshooting steps that helped solve the issue.
Realize that PeerGuardian uses a KEXT.
As strangelydim commented, PeerGuardian (an open source privacy oriented firewall software) uses a kernel extension (KEXT). The KEXT is used to block connections ...
I wasn't able to get my network back by disabling and re-enabling TCP/IP or the Wi-Fi. It seems in my case the computer had gone to sleep with a Juniper VPN connection and when it woke back up the connection had timed out and the routes weren't cleaned up. For me, I had two computers, one working and one not, and so was able to identify the problem after ...