Networking – Can not ping the gateway. Random switching between work and not working

I connected to a new Wifi network 2 days ago. Worked well. All of a sudden, I did not have access to the internet anymore. I've got google google and have temporary failure in name resolution. I pinged the mu gateway and I got no answer. A few hours later, I worked again. Then he stopped working again. I spent 2 hours trying solutions found online now. I have no idea what is causing this. Here is a starting point:

▶ iwconfig 
lo        no wireless extensions.

wlp2s0    IEEE 802.11  ESSID:"fisch"  
          Mode:Managed  Frequency:2.462 GHz  Access Point: 78:54:2E:51:7C:7E   
          Bit Rate=65 Mb/s   Tx-Power=22 dBm   
          Retry short limit:7   RTS thr:off   Fragment thr:off
          Power Management:on
          Link Quality=69/70  Signal level=-41 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:24   Missed beacon:0


▶ cat /etc/hosts
127.0.0.1   localhost
127.0.1.1   lo-skami

# The following lines are desirable for IPv6 capable hosts
::1     ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters


▶ cat /etc/resolv.conf 
# This file is managed by man:systemd-resolved(8). Do not edit.
#
# This is a dynamic resolv.conf file for connecting local clients to the
# internal DNS stub resolver of systemd-resolved. This file lists all
# configured search domains.
#
# Run "resolvectl status" to see details about the uplink DNS servers
# currently in use.
#
# Third party programs must not access this file directly, but only through the
# symlink at /etc/resolv.conf. To manage man:resolv.conf(5) in a different way,
# replace this symlink by a static file or a different symlink.
#
# See man:systemd-resolved.service(8) for details about the supported modes of
# operation for /etc/resolv.conf.

nameserver 127.0.0.53
options edns0


▶ ip r    
default via 192.168.0.1 dev wlp2s0 proto dhcp metric 600 
169.254.0.0/16 dev wlp2s0 scope link metric 1000 
192.168.0.0/24 dev wlp2s0 proto kernel scope link src 192.168.0.103 metric 600


▶ ping www.google.com
ping: www.google.com: Temporary failure in name resolution


▶ ping -c4 8.8.8.8
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.

--- 8.8.8.8 ping statistics ---
4 packets transmitted, 0 received, 100% packet loss, time 52ms


▶ ping -c3 192.168.0.1
PING 192.168.0.1 (192.168.0.1) 56(84) bytes of data.

--- 192.168.0.1 ping statistics ---
3 packets transmitted, 0 received, 100% packet loss, time 44ms


▶ ping -c3 1.1
PING 1.1 (1.0.0.1) 56(84) bytes of data.

--- 1.1 ping statistics ---
3 packets transmitted, 0 received, 100% packet loss, time 13ms

It is this Linux installation that is faulty. I had a parallel start for two distributions. The networking of the other distribution works well.

btw. networking for this faulty distribution has also worked in all other wifi networks on which I was. At least until 2 days ago. I have not checked with other networks since then.

Do you have any idea of ​​the cause of this? Do you need other order outputs or newspapers?

Windows – I can ping my server IP but I can not find the network card

I have a Windows Server 2016 out there, you can see this:

enter the description of the image here

I can ping the IP address of the server, and I can see the network adapter icon in the login page.

But, after connecting Windows Server 2016, I can not find the network card icon at the bottom, but I can ping the IP address of it.

enter the description of the image here

I also can not find a network adapter configuration element in the directory.

t

How to solve this strange problem?

networking – SSH on Ubuntu 18.04.3 will not connect unless I ping the address

I've got 2 raspberry pi that I'd used to connect from Windows via PuTTy. I did not encounter any problem (I can not guarantee, however, because sometimes I could not log in).

Since I use Ubuntu 18.04.3, I have a rather strange behavior. I can not connect to my pi apricot if I do not ping them first.

$ssh pi@10.0.0.37
ssh: connect to host 10.0.0.37 port 22: No route to host

$ping 10.0.0.37
PING 10.0.0.37 (10.0.0.37) 56(84) bytes of data.
64 bytes from 10.0.0.37: icmp_seq=1 ttl=64 time=90.4 ms
64 bytes from 10.0.0.37: icmp_seq=2 ttl=64 time=7.48 ms
64 bytes from 10.0.0.37: icmp_seq=3 ttl=64 time=14.6 ms
64 bytes from 10.0.0.37: icmp_seq=4 ttl=64 time=7.06 ms7

$ssh pi@10.0.0.37
pi@10.0.0.37's password: 

After pinging the pi, I rested for a while, but for no reason, I can not log in anymore.

Does anyone have any idea of ​​what might be causing it?

system domain name – can not name ssh or ping to hostname, but dig and nslookup work in Ubuntu 18.04

I've updated my kernel this weekend and I'm now using version 5.3.1.

christopher@HAL4:~$ uname -r
5.3.1-050301-generic

I have to connect to servers, but I can not do it by hostname anymore. For example, I have a server, "web4" and its local IP address is 192.168.64.140. If I run dig:

christopher@HAL4:~$ dig web4

; <<>> DiG 9.11.3-1ubuntu1.9-Ubuntu <<>> web4
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 1580
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1280
;; QUESTION SECTION:
;web4.              IN  A

;; ANSWER SECTION:
web4.           0   IN  A   192.168.64.140

;; Query time: 0 msec
;; SERVER: 192.168.3.222#53(192.168.3.222) <---- Correct! 
;; WHEN: Mon Sep 30 09:50:31 CDT 2019
;; MSG SIZE  rcvd: 49

Same thing for nslookup:

christopher@HAL4:~$ nslookup web4
Server:     192.168.3.222
Address:    192.168.3.222#53

Name:   web4
Address: 192.168.64.140

However, neither ping nor ssh work ('login' is a bash script that uses my key):

christopher@HAL4:~$ ping web4
ping: web4: Name or service not known
christopher@HAL4:~$ login web4
ssh: Could not resolve hostname web4: Name or service not known 

My /etc/resolv.conf is:

# This file is managed by man:systemd-resolved(8). Do not edit.
#
# This is a dynamic resolv.conf file for connecting local clients directly to
# all known uplink DNS servers. This file lists all configured search domains.
#
# Third party programs must not access this file directly, but only through the
# symlink at /etc/resolv.conf. To manage man:resolv.conf(5) in a different way,
# replace this symlink by a static file or a different symlink.
#


# See man:systemd-resolved.service(8) for details about the supported modes of
# operation for /etc/resolv.conf.

nameserver 192.168.3.222
nameserver 192.168.70.80

This is a symbolic link to /run/systemd/resolve/resolv.conf.

Here is my file /etc/netplan/01-network-manager-all.yaml:

christopher@HAL4:~$ cat /etc/netplan/01-network-manager-all.yaml 
# Let NetworkManager manage all devices on this system
network:
  version: 2
  renderer: NetworkManager
  ethernets:
          enp4s0:
                  dhcp4: no
                  addresses: (192.168.2.47/19)
                  gateway4: 192.168.1.1
                  nameservers:
                          addresses: (192.168.3.222,192.168.70.80)

What happened to my DNS ?!

[Tutorial] New index / ping time


GSA search engine ranking in version 13.91 >_< adding a new feature that allows you to defer sending URLs to indexers and ping server – Learn more about this new feature and its use to save money. time and money – Learn more about this feature in the blog post here.

measure latency / delay with ICMP (ping)

How to measure latency (not real time) using ICMP (ping) on ​​Linux?

Internet Control Message Protocol (ICMP) is a protocol for supporting the Internet Protocol Suite.

networking – How to ping a computer in another subnet?

I have two routers, the router A to 192.168.178.1 and router B that is connected to router A and has the address 192.168.0.1 and 192.168.178.21 in the network of router A.

Now my computer is connected to Router A and my target device is connected to Router B with the address 192.168.0.105.

In Router A, I configured a rule with the network 192.168.0.0subnet mask 255.255.255.0 and gateway 192.168.178.21. Is it correct?

I can not ping the target device from my computer:

ping 192.168.0.105
PING 192.168.0.105 (192.168.0.105) 56(84) bytes of data.
From 192.168.178.1: icmp_seq=250 Redirect Host(New nexthop: 192.168.178.21)

(The second line appears after about a minute and repeats every minute)

Do I need to configure something in Router B? How can I debug this? Thank you.

Networking – What explains the difference in time when I ping a remote server?

The earlier failure had made me doubt the quality of my own connection. Which caused me to ping to SE and I saw something that I can not explain, probably because of a lack of knowledge.

ping -c4 wordpress.stackexchange.com

I get 4 standard enough pings and the following summary:

4 packets transmitted, 4 received, 0% packet loss, time 12121ms
rtt min/avg/max/mdev = 50.612/71.505/82.041/12.522 ms

The ping time is maybe 2% of that total so what is the rest and what does it tell me?

If that makes a difference, ping from an Ubuntu PC with a fiber connection in the UK.

Unable to ping a specific IP address

Hello,

I have a dedicated server at Hetzner located in Germany. For reasons I do not understand, I can not query this specific server:

Code:

# ping 195.225.237.224
PING 195.225.237.224 (195.225.237.224) 56(84) bytes of data.
^C
--- 195.225.237.224 ping statistics ---
2 packets transmitted, 0 received, 100% packet loss, time 1003ms

I have already tried to disable my firewall. I've checked my IP / domain in some blacklists and I'm clean. I really do not know where to look.

iphone – I can use my watch to ping my phone, but how can i use my phone to ping my watch

In fact, there is a way to do this as long as Find My iPhone is enabled in the iCloud settings. If yes, do the following:

  1. On your iPhone, launch the iPhone Find application
  2. In the lower part of the screen, you should see all your devices, including your Apple Watch.
  3. Tap the Apple Watch list
  4. Now at the bottom center of the next screen you will see the word "Actions" – tap this icon
  5. Now press the Play Sound option
  6. Your Apple Watch will now vibrate and play a sound until you reject it

NOTE: You can also do this from other Apple devices or by connecting to iCloud from a web browser on any computer.

For more information, see If Your Apple Watch Is Lost or Stolen on the Apple Web Site.