27 4.220685 192.168.1.104 192.168.1.1 ICMP Destination unreachable (Port unreachable) User Datagram Protocol, Src Port: sip (5060), Dst Port: 5062 (5062)
networking - Disable ICMP Unreachable replies - Server Fault To prevent ICMP unreachable packets being sent, you can drop them using netfilter (iptables): iptables -I OUTPUT -p icmp --icmp-type destination-unreachable -j DROP Better is to prevent them being generated in the first place by using the DROP target on the INPUT traffic, rather than REJECT (or nothing where the kernel networking stack will Troubleshoot TCP/IP connectivity - Windows Client 10.10.10.1 10.10.10.2 UDP UDP:SrcPort=49875,DstPort=3343 10.10.10.2 10.10.10.1 ICMP ICMP:Destination Unreachable Message, Port Unreachable,10.10.10.2:3343 During the course of troubleshooting connectivity issue, you might also see in the network trace that a machine receives packets but does not respond to. What is ICMP? The Protocol, Port Number and PING!
From 192.168.1.91 icmp_seq=4 Destination Host Unreachable. Top. foxb Posts: 1927 Intel Corporation Cougar Point 4 port SATA IDE Controller (rev 05)
ICMP Port unreachable is a code 3 within type 3 3.3. Port Unreachable - generated if the designated transport protocol (e.g., UDP) is unable to demultiplex the datagram in the transport layer of the final destination but has no protocol mechanism to inform the sender ICMP destination unreachable to DNS server? - General
ICMP destination unreachable to DNS server? - posted in General Technical Questions: In the process of tuning our firewall configuration Ive noticed our Barracuda is sending ICMP destination unreachable messages (type 3, code 3) to the DNS servers that its configured for. Why would it do this?I could understand if it was sending these messages to a host that it was trying to relay for, but we
Figure 1 provides an example that demonstrates how Internet Control Message Protocol (ICMP) destination port unreachable messages are generated. In the example, host h1 sends a UDP packet to port 30000 on host h4.The packet message transits switches s1 and s2 on its path to h4.In this case, h4 is not running a service that listens for UDP packets on port 30000, so host h4 sends an ICMP networking - Linux PCs sending "ICMP udp port unreachable 2) (untested) drop on the OUTPUT chain ICMP-unreachable packets going to port UDP/53 I would suggest the former to be the preferable solution, and this probably accounts for why you don't tend to see this coming from Windows machines (which have a local cache) icmp type 3 code 3 port unreachable when trying to - J icmp type 3 code 3 port unreachable when trying to connect to ike (port 500) on SRX 08-16-2017 11:39 PM There is an IPSEC tunnel from a SRX240H2 to a Sophos UTM 9. Container - Destination Port Unreachable | Proxmox Support