Why is my DHCP server not releasing client address leases?

Why is my Softether VPN not working?

You may have seen a warning about 'Softether software has detected your browser as being infected with spyware' when trying to access a website or download files.

Softether has been reporting false positives like this for some time now, and it appears that these reports are coming from a network of botnets known as Neutrino. The Neutrino network is notorious for hijacking web browser cookies which in turn results in the warning above. To prevent this, we recommend installing an ad-blocking plugin (eg Adblock) or using another VPN service.

If you would like to know more, you can read this technical blog post from Softether regarding the security issues that have been happening over the past few months. How do I stop getting this warning? If you wish to not receive these warnings, you can prevent them by downloading an ad-blocking plugin. Please see our other posts on ad-blocking plugins.

Download the uTorrent softether plugin. What is wrong with the uTorrent plugin? In late 2024, a vulnerability was discovered in the Softether uTorrent plugin. This bug was fixed on December 29, 2024 but if you are still receiving the warning, the plugin is likely not working for you. To make sure that the plugin is running properly, please check that the following are enabled.

For Windows: Start -> Control Panel -> Software and Features. UTorrent -> Plugins -> Softether (and tick Enable plugin). For macOS: Software & Updates -> Mac App Store. UTorrent -> Plugins -> Softether (and tick Enable plugin). How do I uninstall the plugin? On macOS: In the Finder, enter ~/Library/Application Support/uTorrent/Plugins and drag the Softether folder to the Trash. If you are unable to find this folder, open the terminal app, type cd, and press Enter. Next type rm -r /usr/local/libexec/uTorrent/Plugins, where the path is the path to the plugin, and then press Enter.

On Windows: Right-click on the shortcut for uTorrent and click on Properties.

Why is my DHCP server not releasing client address leases?

We have an Ubuntu Server (Karmic) and we are experiencing an issue with DHCP leases being held on the subnets. The client will get a lease, but it does not get released. It does give them a new IP address for a period of time, but eventually it starts timing out. We have checked the syslog, and we see the following lines.

Jan 21 08:47:35 kdc dhcpd: DHCPREQUEST for 10.16 via eth0 Jan 21 08:47:35 kdc dhcpd: DHCPOFFER 10.16 from 10.1
Jan 21 08:47:35 kdc dhcpd: DHCPACK 10.16 Jan 21 08:47:45 kdc dhcpd: DHCPREQUEST for 10.16 via eth0 Jan 21 08:47:45 kdc dhcpd: DHCPACK 10.17 via eth0 Jan 21 08:47:50 kdc dhcpd: DHCPREQUEST for 10.17 via eth0 Jan 21 08:47:50 kdc dhcpd: DHCPACK 10.18 via eth0 Jan 21 08:48:08 kdc dhcpd: DHCPREQUEST for 10.18 via eth0 Jan 21 08:48:08 kdc dhcpd: DHCPACK 10.19 via eth0

Why is my DHCP not working?

I am connecting to my home router with a wireless card, so I do not know what kind of "switch" my router is.

I am running Ubuntu 14.04 and have the same problem on my laptop. Can someone help me get it working please?

The problem: DHCP fails to connect to the internet. The first thing to try would be to switch your wifi card to managed mode in the Network manager rather than "ad-hoc" mode. You may find this will improve connection stability and speed (this should fix any network specific problems but there may be other issues depending on how your network is configured).

If you are using Ubuntu 14.04 I would suggest that you install dhcpcd and run a command like this: sudo dhcpcd -v -e enp0s25. This should print some debug messages as the internet connection tries to connect. If there is a problem, the connection will drop, then it will reconnect. Hopefully this will show you where the problem is.

You can also try just using sudo dhclient enp0s25 instead. You can then get a bit more detailed info by adding an eth0 and/or eth0:avahi entry to /etc/network/interfaces. The command for the latter is sudo ifconfig -a