Unknown USB device (device descriptor request failed).
In Bluetooth & devices > Devices in the Settings interface, under the Input section, the device with the keyboard icon says, “unknown USB device (device descriptor request failed)”.
| Layer | Protocol data unit (PDU) | Function | Common Protocols | ||
|---|---|---|---|---|---|
| Host layers | 7 | Application | Data | High-level protocols such as for resource sharing or remote file access, e.g. HTTP. | DNS, HTTP, HTTPS, FTP, POP, IMAP, SMTP, SNMP |
| 6 | Presentation | Translation of data between a networking service and an application; including character encoding, data compression and encryption/decryption | MIME, SSL/TLS, XDR | ||
| 5 | Session | Managing communication sessions, i.e., continuous exchange of information in the form of multiple back-and-forth transmissions between two nodes | Named pipe, NetBIOS, SAP, PPTP, RTP, SOCKS, X.225, Domain Name Sytem, Remote Procedure Call, Network File System | ||
| 4 | Transport | Segment, Datagram | Reliable transmission of data segments between points on a network, including segmentation, acknowledgement, and multiplexing | TCP, UDP, SCTP, DCCP, SPX | |
| Media layers | 3 | Network | Packet | Structuring and managing a multi-node network, including addressing, routing and traffic control | IP (IPv4Internet Protocol version 4 (IPv4) IPv4 address classes Predefined ranges of IP addresses (Classes A, B, C, D, and E) designed to allocate addresses based on network size, with Class A for large networks, Class B for medium-sized networks, Class C for small networks, Class D for multicast, and Class E reserved for experimental use.PublicClassRangeSubnet MaskCIDR notationA0. 0.0.0 – 126.255.255.255255.0.0.0 B128.0.0.0 – 191.255.255.255255.255.0.0 C192. 0.0.0 – 223.255.255.255255.255.255.0 D224.0.0.0 – 239.255.255.255 E240.0.0.0 – 255.255.255.255 PrivateClassRangeSubnet MaskCIDR notationA10. 0.0.0 – 10.255.255.255255.0.0.010.0.0.0/8B172.16.0.0 – 172.31.255.255255.255.0.0172.16.0.0/16C192.168.0.0 – 192.168.255.255255.255.255.0192.168.0.0/24Loopback RangeRangeSubnet maskCIDR notation127.0.0.0–127.255.255.255255.0.0.0127.0.0.0/8127.0.0.1Automatic Private IP Addressing (APIPA; aka Link-Local address)RangeSubnet maskCIDR notation169.254.0.0 – 169.254.255.255255.255.0.0169.254.0.0/16Internetwork Broadcast Address255.255.255.255Network Broadcast Addressx.x.x.255, IPv6), ICMP, IPsec, IGMP, IPX, IS-IS, AppleTalk, X.25, PLP, RIP |
| 2 | Datalink | Frame | Transmission of data frames between two nodes connected by a physical layer | ATM, ARP, Synchronous Data Link Control, High-Level Data Link Control, CSLIP, Serial Line Interface Protocol, GFP, PLIP, IEEE 802.2, LLC, MAC, L2TP, IEEE 802.3, Frame Relay, ITU-T G.hn DLL, Point-to-Point Protocol, X.25 LAPB, Q.922 Link Access Procedure, STP | |
| 1 | Physical | Bit, Symbol | Transmission and reception of raw bit streams over a physical medium | RS-232, RS-449, ITU-T V-Series, I.430, I.431, PDH, SONET/SDH, PON, OTN, DSL, IEEE 802.3, IEEE 802.11, IEEE 802.15, IEEE 802.16, IEEE 1394, ITU-T G.hn PHY, USB, Bluetooth | |
How-To Install YouTube/YouTube Music/YouTube TV Apps on Microsoft Windows
YouTube doesn’t offer apps in the Microsoft Store, but they do support Native App installation via web browsers that looks and feels like an app offered from the Microsoft Store.
Some Joomla extensions do not completely uninstall their plugins, modules, and component, directories, and files. These extensions can include VirtueMart and AdminTools. This can interfere with and disrupt the Joomla update checker process by continuing to search for extension that have been partially uninstalled and don’t exist in the system.
Joomla extensions store data in both the database and the file system.
Extension files are store in the following file system directories:
Extension files are stored in the database
There could be other data store in the database depending on the type of extension that was installed. Some extensions offer different content types. If any residual data is left in the database, it ould be stored in the _content_type table.
Short answer: No, VLANs and router by default don’t forward broadcast or ARP Requests to devices outside of their network. Yes, Layer 2 switches, do forward broadcast and ARP Requests.
Explanation: VLANs and router create and represent separate broadcast domains. A broadcast domain is a logical division of a computer network where all devices can communicate with each other by sending broadcast messages at the data link layer (Layer 2 of the OSI model). This means that any broadcast sent by a device within this domain is received by all other devices in the same domain, but not by devices in different broadcast domains. Typically, all devices connected to the same Ethernet switch or hub are part of the same broadcast domain, while routers separate different broadcast domains to manage traffic and reduce congestion.
Add the following code to the functions.php file in your child theme’s directory.
remove_action(‘wp_head’, ‘wc_generator’);
remove_action(‘wp_head’, ‘wp_generator’);
remove_action(‘wp_head’, ‘perflab_render_generator’);
For security purposes, you should ensure that sensitive directories like /vendor are not exposed by properly configuring your web server.
Likely, the best method for making your Drupal site accessible via the root directory (/) is by pointing your domain to the /web directory, i.e. making the /web directory the root directory.
Another method to install Drupal in the root directory is to modify the composer.json file before running composer install.
To install drupal in root (/) directory instead of web (/web) directory, you must:
If you need more help, follow the instructions in our tutorial: Install Drupal CMS in Root Directory.
Location of IPv4Internet Protocol version 4 (IPv4) IPv4 address classes Predefined ranges of IP addresses (Classes A, B, C, D, and E) designed to allocate addresses based on network size, with Class A for large networks, Class B for medium-sized networks, Class C for small networks, Class D for multicast, and Class E reserved for experimental use.PublicClassRangeSubnet MaskCIDR notationA0. 0.0.0 – 126.255.255.255255.0.0.0 B128.0.0.0 – 191.255.255.255255.255.0.0 C192. 0.0.0 – 223.255.255.255255.255.255.0 D224.0.0.0 – 239.255.255.255 E240.0.0.0 – 255.255.255.255 PrivateClassRangeSubnet MaskCIDR notationA10. 0.0.0 – 10.255.255.255255.0.0.010.0.0.0/8B172.16.0.0 – 172.31.255.255255.255.0.0172.16.0.0/16C192.168.0.0 – 192.168.255.255255.255.255.0192.168.0.0/24Loopback RangeRangeSubnet maskCIDR notation127.0.0.0–127.255.255.255255.0.0.0127.0.0.0/8127.0.0.1Automatic Private IP Addressing (APIPA; aka Link-Local address)RangeSubnet maskCIDR notation169.254.0.0 – 169.254.255.255255.255.0.0169.254.0.0/16Internetwork Broadcast Address255.255.255.255Network Broadcast Addressx.x.x.255 file: /etc/sysconfig/iptables
Location of IPv6 file: /etc/sysconfig/ip6tables
Linux Command to Access Them Directly
Linux Command to Get to Directory