Our TCP timeout value is 900 minutes, by the way, for reference. I suspect some previous administrator changed the TCP settings but forgot/ignored the UDP settings. The NSA logs also have messages about UDP packets being dropped, as well, both incoming and outgoing. ![]() RESOLUTION: Step 1: Log into the SonicWall firewall. Step 2: Go to Firewall Settings| Advanced. Step 3: Scroll down to the section called UDP. Step 4: Modify the default UDP Connection Timeout, to the desired value. Please, be aware that this modification will only apply to new connections (firewall rules, etc). Resolution for SonicOS 6.5 and Later SonicOS 6.5 was released September 2017. This release includes significant user interface changes and many new features that are different from the SonicOS 6.2 and earlier firmware. The below resolution is for customers using SonicOS 6.5 and later firmware. Log into the SonicWall firewall. • Click Manage in the top navigation menu • Go to Firewall Settings| Flood Protection. ![]() • Click on UDP Tab. • Under UDP Settings • Modify the default UDP Connection Timeout, to the desired value. • Click on Accept to save the changes Please, be aware that this modification will only apply to new connections (firewall rules, etc). In Windows the value is dynamic for established conections, though the default for initial connections is 72 seconds. The Registry settings are defined in this article: HKEY_LOCAL_MACHINE SYSTEM CurrentControlSet Services: Tcpip Parameters TcpInitialRTT: Defines what the initial time-out settings are for new connections. Photos for mac download. This number in seconds is doubled each time it retransmits before timing a connection out. Defaults to 3. TcpMaxConnectRetransmissions: Defines the number of retransmissions before timing a connection out. Defaults to 5. Usually 'connect timeout' refers to the timeout for creating the initial connection to a host. In many systems (Windows 7 included), this value is configured using separate settings from timeouts for ongoing communications after a connection has been established. This answer addresses the 'initial connect' scenario for Windows 7, which is different from XP. For Windows 7, two hotfixes are required to support adjusting connect timeout settings. The new settings can be configured with the 'netsh' command. • • From the 2786464 hotfix article: Note In Windows 7 and Windows Server 2008 R2, the TCP maximum SYN retransmission (JH: MaxSynRetransmissions) value is set to 2, and is not configurable. Because of the 3-second limit of the initial time-out value (JH: InitialRTO), the TCP three-way handshake is limited to a 21-second timeframe (3 seconds + 2*3 seconds + 4*3 seconds = 21 seconds). The first hotfix adds a 'MaxSynRetransmissions' setting which allows changing the retry setting from the default value of 2. The second adds 'InitialRto' setting which allows changing the Initial RTO value from the default of 3000ms (yes, milliseconds), but only to something shorter than 3000ms; it cannot be increased. Depending on your situation, you may only need the 'MaxSynRetransmissions' hotfix. Install both hotfixes, reboot, then open a command window as Administrator. Further reboots are not required for subsequent netsh command invocations. C: Windows system32>NET SESSION >nul 2>&1 C: Windows system32>IF%ERRORLEVEL% EQU 0 (ECHO Administrator PRIVILEGES Detected!) ELSE ( ECHO NOT AN ADMIN! ) Administrator PRIVILEGES Detected! C: Windows system32>netsh interface tcp show global Querying active state. & telnet 192.168.1.254 & echo!TIME!' 14:10:30.53 Connecting To 192.168.1.254.Could not open connection to the host, on port 23: Connect failed 14:10:51.60 C: Windows system32>netsh interface tcp set global MaxSynRetransmissions=3 Ok. C: Windows system32>netsh interface tcp show global Querying active state. TCP Global Parameters ---------------------------------------------- Receive-Side Scaling State: enabled Chimney Offload State: automatic NetDMA State: enabled Direct Cache Acess (DCA): disabled Receive Window Auto-Tuning Level: normal Add-On Congestion Control Provider: none ECN Capability: disabled RFC 1323 Timestamps: disabled Initial RTO: 3000 Non Sack Rtt Resiliency: disabled Max SYN Retransmissions: 3 ** The above autotuninglevel setting is the result of Windows Scaling heuristics overriding any local/policy configuration on at least one profile. C: Windows system32>cmd /v:on /c 'echo!TIME! & telnet 192.168.1.254 & echo!TIME!'
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