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0 votes

is a tap interface on linux vulnerable to snooping attacks

I believe every Qemu instance, e.g. every VM will need its own tap interface. I doubt it is possible to run multiple VMs and use a single tap for that. Anyway, putting an interface inside a VM into a ...
1 vote

Can you find out why connection refused happens if you are not the sender of request?

When a client attempts to connect to a service/server there are roughly the following scenario's: The connection succeeds. The connection attempt fails, because the client receives no response. It ...
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Cannot ping own ip from its linux network namespace

Fix: sudo ip -n nsa link set lo up sudo ip -n nsb link set lo up Note that the ping-s in the question above were not directed to loopback. Nevertheless, if loopback interface is down, the ping to ...
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SMB Connection to Server fails with "The Network path was not found", SMB attempts to connect over HTTP

Please try this: Enabling TCP/IP NetBIOS Helper Service made everything work again. Windows Key + R > Services.msc > Find TCP/IP NetBIOS Helper and make sure it's started and set to automatic. ...
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Bash: Checking if can sudo on remote host using sshpass; how 'exposed' is the password?

try to run sshpass at local (for remote sudo), but failed 1. test sudo without ssh //ok $ SSHPASS=your_passwd sshpass -e sudo id uid=0(root) gid=0(root) groups=0(root) sudo with ssh //fail SSHPASS=...
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ARP Command doesn't display all devices

As a previous answer has stated, "arp -a" in the command line is not sufficient ("mac adress is added to arp table only after you send something to that machine"). I think nmap (...
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Hyper V Dedicated Network Traffic for Hyper V Replication between two Hyper V Server

This seems like overkill to me to be honest, but the answer to your question is just to configure the 10G SFP+ ports with IPs in a subnet which is specific to them, and then configure the Hyper-V ...
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1 vote

VMWare Workstation - Changing subnet settings for host-only network from Class C to Class B ( 255.255.255.0 to 255.255.0.0) on Windows Host

The error message is pretty clear: according to your subnet mask, you have 16 bits for the network address and 16 bits for the host address. However, your Subnet IP has some bits in the host part of ...
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Why are workstations trying to access file server port 445 on the isolated iSCSI subnet?

The server has registered the IP addresses of the iSCSI interfaces with DNS. On the adapter properties for the iSCSI interfaces, turn that off and delete the entries from DNS.
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DHCP logs showing (no free leases)

You have deny unknown-clients in your pool configuration, which means clients can only receive an address from DHCP if they have a static DHCP reservation defined for their MAC address in a host ...
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How to connect a MacOS client to Linux WireGuard Server

Change AllowedIPs value in client configuration to 0.0.0.0/0. Also you don't need ListenPort in client configuration.
2 votes
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Add ipv6 to Read Hat 9 loopback interface

This has nothing to do with RHEL 9. The Vagrant image that you're using explicitly disabled IPv6; take a look at /etc/sysctl.conf: [root@node1 sysctl.d]# cat /etc/sysctl.conf # sysctl settings are ...
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Testing UDP port connectivity

You can check a specific UDP port using the following command: nmap <hostname or ip> -sU -pU:<UDP port>
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Why is networkd changing the MAC addresses of my bonded interfaces?

Here is sample interface and bond file config, MACADDR may solve your issue. #Redhat/Centos # cat /etc/sysconfig/network-scripts/ifcfg-eno1 DEVICE=eno1 NAME=eno1 TYPE=Ethernet BOOTPROTO=none ONBOOT=...
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Ansible 'ping' fail - 'session request sent', but 'read header failed: Broken pipe'

According the output provided it seems that you try to establish a SSH connection to a switch. Such devices may not have all capabilities for Python scripts. Because of ping module – Try to connect to ...
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1 vote
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Running Ansible tasks (ex: get_url) within a network namespace

Regarding Is there some sort of Ansible task override to handle this scenario? Yes, there is. Depending on how one look on it, it is quite simple. The solution lays within the Become plugins. ...
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How can I display the IP address of an interface?

On MacOS I use ipconfig getifaddr <interface-name> The command is listed under the BSD System Manager's Manual.
5 votes
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How is it possible that I'm getting a 13ms ping RTT from London to a New York IP?

As far as I can tell that IP-address 172.67.143.96 is a CloudFlare IP-address and not the actual IP-address of you server. CloudFlare in turn uses anycast or similar to direct your traffic to a nearby ...
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1 vote

How can I get the IP address IPV4/IPV6 on linux

I want to register with third party API and that needs the IP address of system where my application is running. Then asking: I need to read the IPV4/IPV6 address and it should work for any Linux ...
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1 vote

All IPv6 prefixes that should be routed by a public router

All Global IPv6 addresses are in the 2000::/3 range. There are a few ranges inside the Global address block that are not Globally Reachable. See the IANA IPv6 Special-Purpose Address Registry. There ...
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1 vote
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All IPv6 prefixes that should be routed by a public router

The 2000::/3 prefix is where all of the Global Unicast addresses reside and may be what you want. There may be other prefixes you could add (but it seems unlikely) see IPv6 Address Types.
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How can I get the IP address IPV4/IPV6 on linux

RTNETLINK answers: Network is unreachable ping -a 1.2.3.4 whois 1.2.3.4 And if you want to see the network path: traceroute 1.2.3.4
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How can I get the IP address IPV4/IPV6 on linux

I prefer hostname and ip on our GNU/LINUX Debian based distros In the past i used ifconfig but now is replaced with ip and is not longer available on the most basic installations of GNU/LINUX Debian ...
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When NOT to use Azure Virtual WAN?

I think virtual wan is overkill when you are not in multiple regions,or not use a multi region architecture.
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1 vote

How can I get the IP address IPV4/IPV6 on linux

Using curl, I'd use ipinfo.io $ curl -s ipinfo.io | grep -Po 'ip[^0-9]*"\K[^"]*' 12.34.56.78 or $ curl -s ipinfo.io | sed -En '/ip/s/[^0-9]*"([^"]*).*/\1/p' 12.34.56.78 This ...
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Why Can't I access my website ,even if 80 port of my ecs server is open?

If you are trying to access your ECS server securely (ssl connection), you might need to also open TCP port 443 to allow your browser to use https.
2 votes

How can I get the IP address IPV4/IPV6 on linux

There is no single command that works on every Linux / Unix variant. FreeBSD-based systems for example use ifconfig. Earlier Linux used ifconfig. ip was added later as a replacement, but one cannot ...
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How can I get the IP address IPV4/IPV6 on linux

Simple: ip addr will return both ipv4 and ipv6 addresses for all network interfaces. To get ipv4 only use -4. Like ip -4 addr. To get ipv6 only you need to use -6. Like: ip -6 addr. To get the ipv4 ...
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Every four hours after reboot TCP connections fail to establish, while ICMP ping is still OK

I don't know why it was happening with this exact time interval but I finally discovered that I have same IP in the network. It's a surprising thing for me that system doesn't signal about identical ...
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show all users on a Catalyst Cisco switch

To list all users: "show running-config | include username" If usernames are using secrets command to reset user secret: "username %username% secret 0 %secret%"
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How can I display the IP address of an interface?

This is what I use: ip r s | awk '/eth0/ {print $7}' will print, for example: 192.168.0.1
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0 votes
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How to route host traffic over lxc?

Well I just solved it by simply restarting the firewall service until the default policies applied. I add the following statements to my startup script: until $(iptables -t nat -L PREROUTING |grep -q '...
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1 vote
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Configuring Ubuntu 22.04 to generate the interfacepart of an IPv6 staticly

IPv6 has a few choices for how to do stable IP addresses. Defining a static interface ID on the host. DHCPv6 where reservations persist. And a value that can be computed from known values, like EUI-64 ...
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Can't communicate between multiple interfaces on same subnet

Beside various minor issues the issue is about policy routing: one must distinguish the route for an egress packet from the route for an ingress packet with exactly the same content: they use two ...
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Setting the hostname: FQDN or short name?

Short answer: I generally use the FQDN as the hostname (as recommended on RH6/7 docs). However, the more righteous approach would be to use a single-label name as the hostname, setting the FQDN via /...
3 votes
Accepted

DNS Naming clash between TXT Record and CNAME/A-Record

This is actually expected behaviour. RFC1034 has this information: Wildcard RRs do not apply: When the query is in another zone. That is, delegation cancels the wildcard defaults. When the query ...
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How to route host traffic over lxc?

What you need is so called NAT hairpinning (aka NAT loopback, NAT reflection): NAT loopback, [...] is a feature in many consumer routers which permits the access of a service via the public IP address ...
1 vote

DNS Naming clash between TXT Record and CNAME/A-Record

Try _acme_challenge.<mysubdomain1> IN TXT -> any value <mysubdomain1> IN CNAME -> <mysubdomain2>.<mydomain>.com <mysubdomain2> ...
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1 vote

Trouble connecting to the internet with direct connection to the modem

The way I seen your post is; you expect the broadband modem to be act as a router. The fact you receive no IP make me think the modem is in bridge mode. While it's not what you want, I strongly ...
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2 votes
Accepted

Assert if a port is open to host, LAN, or the Internet

From the host itself you can not reliably check if an external firewall or security rule blocks access. Additionally an external check can’t easily distinguish between the server itself or a network ...
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Assert if a port is open to host, LAN, or the Internet

Use tools like nmap, netstat, and tracert. Netstat shares the state of open ports local to the machine it is run on. Tracert is traceroute that traverses the network, sharing if an IP and port are ...
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Assert if a port is open to host, LAN, or the Internet

I would use something like wireshark or nmap, as far as internet goes you need to use portforward port 8877 in your router to your server IP address
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NetBIOS Name Service requests not being sent or answered

I had a problem that several computers could not access SMB share on old Windows 95 (yep, I know...) machine networked on a separate VLAN without internet connectivity. Few computers were able to ...
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Windows Server 2016 Active Directory : A computer with a specific user can see all the network

If it's a rights problem : Did you configure groups to access those data ? Maybe the user has asministrator rights or is part of a group that can access all the network ? Or if it's a network problem :...
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What is virtual tunnel interface "tunl0"?

A tunl<N> interface is generally one used by the kernel's IP-in-IP encapsulation support. This is sometimes used to implement overlay networks -- e.g, in Calico, which can be used with both ...
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How can I restrict SSH access to a hostname rather than an IP address without additional software? [debian-server]

Try hosts.deny and hosts.allow file. You can use both ip wild card and as well as dns name wild cards. #FILE: /etc/hosts.deny(it will deny requests from 192.168.1.* and *.abc.com for ssh) sshd : 192....
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