Dev Stack Source

Answer : Not sure if the question is still relevant, but still wanted to share the result of my investigation.. I just switched from a Cable ISP to Bell Fibe, for both TV and Internet. Bell still don't have Fibre to home in my area, so is is still somewhat a DSL type connection. Bell provided a HUB2000 integrated modem/router. the device is very user friendly, but all advanced network features are blocked.... as expected. I had my entire network already set up as with my previous internet provider (Videotron only provided a cable modem) and i wanted to maintain the same configuration (firewall, IPs, etc).. So this is what I have done: TV receiver is connected via a network cable to the HUB2000 LAN port (as per the original Bell set up) HUB 2000 is connected to the phone line to act as a DSL modem (as per the original set up) WAN port of my MikroTik router is connected to one of the LAN ports of the HUB 2000. Now here is the trick, in my Mikrotik WAN configuration, in...

Answer : This is caused by a change for security reason in kernel 3.18 [1]. There are two ways to fix this. First approach is adding this rule to the file /etc/ufw/before.rules before the line # drop INVALID packets ... -A ufw-before-input -p 47 -j ACCEPT Second approach is manually loading the nf_conntrack_pptp module. You can do this by running sudo modprobe nf_conntrack_pptp To load this module on every boot on Ubuntu, add it to the file /etc/modules . For more recent versions of ufw a solution is instead: sudo ufw allow proto gre from [PPTP gateway IP address] sudo systemctl restart ufw Add nf_conntrack_pptp to /etc/modules-load.d/pptp.conf One liner echo nf_conntrack_pptp | sudo tee /etc/modules-load.d/pptp.conf Explanation The accepted answer works for me, especially the 2nd suggestion--loading the nf_conntrack_pptp kernel module--as opposed to modifying my iptables firewall. My laptop firewall is otherwise unmodified. sudo ufw enable without excepti...

Answer : This means the other side is using another version of TLS and you are using an older version. Set up security attribute to TLS12 before making the connection. This is a widely known problem, as many providers start using TLS12 (e.g. paypal,amazon and so on). ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12; Here is the solution, set in the registry: [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\KeyExchangeAlgorithms\Diffie-Hellman] "ClientMinKeyBitLength"=dword:00000200 as noted here If you are using SslStream, then you need to explicitly set the TLS version in the AuthenticateAsClient call, for example: ssl.AuthenticateAsClient(url, null, SslProtocols.Tls12, false);

Answer : This method checks whether mobile is connected to internet and returns true if connected: private boolean isNetworkConnected() { ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE); return cm.getActiveNetworkInfo() != null && cm.getActiveNetworkInfo().isConnected(); } in manifest, <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" /> <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /> Edit: This method actually checks if device is connected to internet(There is a possibility it's connected to a network but not to internet). public boolean isInternetAvailable() { try { InetAddress ipAddr = InetAddress.getByName("google.com"); //You can replace it with your name return !ipAddr.equals(""); } catch (Exception e) { return false; } } Check to make sure it is...

Answer : This all looks normal to me. Anything under 10.0.0.0/8 (and also 172.16.0.0/12) are perfectly normal NAT addresses. When you put your VMs in NAT mode, the software is essentially acting as it's own dhcp server for the guest machines and will do translations to the host network, so that all the guests on a particular host share an IP with the host. Anything in any of those ranges are fair game for NAT. It appears that VMWare uses a 192.168.0.0/24 range by default, and VirtualBox uses a 10.0.0.0 range. Both are just fine, and neither is better than the other (though I personally prefer 10.0.0.0 ranges because there are 255 times more addresses available). It sounds like maybe you expected NAT mode to use the NAT between your host network and the internet, but that just doesn't happen. In fact, that is what bridge mode does. Switching to bridged mode means your VM guests are now connected directly to your home router's dhcp server for addresses. VirtualB...

Answer : Most modern hardware – Ethernet switches and computer Ethernet interfaces – implements Auto-MDIX, automatically choosing the correct mode for each physical connection. (This is now a required part of Gigabit Ethernet, but also very common among 100 Mbps ports as well.) In other words, you can use the same type – regular straight-through cables – practically everywhere. Ethernet hubs, however, do not have this feature. They do not participate in link negotiation and only electrically connect all the devices. (Although your devices are probably switches mislabelled as hubs, not actual hubs.) Without this feature, two hubs or switches (just like two computers) would have needed a cross-over cable. That is, unless one switch had a dedicated 'Uplink' port, which would accept a straight-through cable instead. (Sometimes the last port had a physical toggle button for this.) I bought super cheap hubs from China so I'm honestly not even sure whether they have that ...

Answer : I faced the same problem in my network. When you use this command: ping icecream It uses WINS server since you have used icecream not icecream.my.domain . When looking for such words, Windows looks for NETBIOS names, but when you look for complete domain records, it will look in the DNS server. You can use one of the solutions below: Make sure you have correct records for that station in your WINS server. Use the complete domain name instead of using the host file. E.g. icecream.my.domain You don't have DNS suffixes configured. Either configure them, or use FQDN like this and it should work: ping icecream.my.domain

Answer : While this question is old, there's no really comprehensive answer. So I'm adding one. In the passive FTP mode (the most common mode nowadays), the FTP server listens on port 21 for an FTP control connection. But for all data transfers, including directory listings, it listens on an additional port. The port is picked out of a configured port range. If you open only the 21 control port on the firewall, you get the described behavior. You can connect, but you cannot list directories or transfer files. For details, see my article on Network configuration for passive FTP mode. You have to go to Control Panel > System and Security > Windows Firewall > Advanced Settings > Inbound Rules > New Rule and add a new inbound rule for data port range your FTP server is using. The port range that the FileZilla FTP server is using, is configured in Edit > Settings > Passive mode settings > Use custom port rage . You can configure a narrow range (like 10 p...

Answer : The problem you are experiencing is due to interference caused by RF overlapping channels. 802.11 RF Channel Specification: The IEEE 802.11 standard establishes several requirements for the RF transmission characteristics of an 802.11 radio. Included in these are the channelization scheme as well as the spectrum radiation of the signal (that is, how the RF energy spreads across the channel frequencies). The 2.4-GHz band is broken down into 11 channels for the FCC or North American domain and 13 channels for the European or ETSI domain. These channels have a center frequency separation of only 5 MHz and an overall channel bandwidth (or frequency occupation) of 22 MHz. This is true for 802.11b products running 1, 2, 5.5, or 11 Mbps as well as the newer 802.11g products running up to 54 Mbps. The differences lie in the modulation scheme (that is, the methods used to place data on the RF signal), but the channels are identical across all of these products. There is also a g...

Answer : The easiest way to configure this would be to use a Multi-WAN router such as the Linksys RV042. Technically: yes In practice, it's an exotic and expensive configuration. You can put more than one address on an interface or use more than one interface and be multihomed . However, this is much more likely to be effective for a big server cluster in a data center. Expensive routers capable of running routing protocols will be needed and then it still would not help you with a single given TCP connection. If you try this as a single user of two retail ISPs, then you will have two different IP addresses, so incoming traffic will use the one you made the outbound connection on, and it's unlikely that any equipment you have can be configured with more than one gateway. A large site with a /24 or shorter prefix and their own ASN can actually announce a single IP address over multiple networks, but that won't work without being further upstream than a retail...

Answer : I had the same exact issue. Looks like you're missing drivers for the Ethernet. Go to this link (which is from the actual Ethernet provider): https://www.realtek.com/en/component/zoo/category/network-interface-controllers-10-100-1000m-gigabit-ethernet-pci-express-software Download the "2.5G Ethernet LINUX driver r8125 for kernel up to 5.6" and follow the installation instructions. You should be able to use wired connection once you're done. The rtl8125b support has been added to the linux-next tree 6 days ago. https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/drivers/net/ethernet/realtek?h=next-20200720&id=0439297be95111cf9ef5ece2091af16d140ce2ef It will take some time to get into stable and then into Ubuntu. You can try to install drivers from the Realtek site before Linux supports it natively. You'll need to disable Secure Boot in BIOS and blacklist r8169 to get them working. The issue is fixed in the 5.9 kern...