I just got a new router and internet connection.
My phone and my second computer have no problem to connect to internet (wifi or cable). My first computer, where I am running Limux Mint 18.1 Serena, can connect with cable or wifi but I am unable to browser.
I can ping 8.8.8.8 but not google.com.
I do not understand much of DNS but I tried to follow some online tutorials.
I tried to modify the /etc/resolconf directory by adding a resolv.conf file with a new servername but didn't work (even after restarting network-manager). I tried as well to modify the /etc/resolv.conf.d/tail file (as read in other tutorials) by adding a new servername but still not working.
Any suggestion?
Your DNS resolving doesn't work.
Check your firewall for an open port UDP/53 to 8.8.8.8
# iptables -L -n -v
Check with your ISP for DNS server provided. They are probably blocking UDP/53 somewhere on the way out to force you to use internal DNS server.
If you are on DHCP, renew the lease.
Depends on distro (most probably networkmanager, ifdown/ifup combination may work as well). This happens quite often with resolvconfd and dnsmasq. You may need to restart the NetworkManager then
Again - command depends on distro, usually with systemd
# systemctl restart NetworkManager
If you are on static IP and have noone to ask or check their config, you may sniff (tcpdump -nnvv -i <interface> udp port 53).
The problem occurs due to trouble with DNS setting
If you are using linux follow:
Clear this file content (root permission required)
nano /etc/resolv.conf
Add the folling text:
nameserver 1.1.1.1
nameserver 8.8.8.8
Save and Reboot
If using Windows Follow:
Control Panel\Network and Internet\Network and Sharing Center
Select current active connection (wifi/broadband)
Properties > Networking > ipv4 > custom dns > 1.1.1.1 & 8.8.8.8
check Validate setting upon exit > save
Related
I am very unfamiliarized with linux and I have a spare pc lying around, I installed Ubuntu Server 20.04.4 LTS. It's all connected to the internet and I have verified that, but when I run:
terraria#mc-ubuntu:~$ wget https://terraria.org/api/download/pc-dedicated-server/terraria-server-1436.zip -O server.zip
all that it gives me is this that of which I have no clue what to do:
wget: unable to resolve host address 'terraria.org'
I need help, and yes I have tried in root, same output.
I checked if mentioned file exists using --spider option
wget --spider https://terraria.org/api/download/pc-dedicated-server/terraria-server-1436.zip
output
Spider mode enabled. Check if remote file exists.
--2022-06-28 10:19:47-- https://terraria.org/api/download/pc-dedicated-server/terraria-server-1436.zip
Resolving terraria.org (terraria.org)... 188.114.96.13, 188.114.97.13
Connecting to terraria.org (terraria.org)|188.114.96.13|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 43392536 (41M) [application/zip]
Remote file exists.
so URL you have used seems to be correct, therefore I suspect issue with DNS lookup. wget is unable to find IP address corresponding to terraria.org. You need to add some nameserver aware of terraria.org to /etc/resolv.conf file, I suggest trying Google one that is add following line
nameserver 8.8.8.8
to /etc/resolv.conf then write if it did help (I do not have ability to test that)
I have two separate clusters (Application and DB) in the same namespace. Statefulset for DB cluster and Deployment for Application cluster. For internal communication I have configured a Headless Service. When I ping from a pod in application cluster to the service it works (Works the other way round too - DB pod to service works). But sometimes, for example if I continuously execute ping command for like 3 times, the third time it gives an error - "ping: : Temporary failure in name resolution". Why is this happening?
As far as I know this is usually a name resolution error and shows that your DNS server cannot resolve the domain names into their respective IP addresses. This can present a grave challenge as you will not be able to update, upgrade, or even install any software packages on your Linux system. Here I have listed few reasons
1.Forgot configuring or Wrongly Configured resolv.conf File
The /etc/resolv.conf file is the resolver configuration file in Linux systems. It contains the DNS entries that help your Linux system to resolve domain names into IP addresses.
If this file is not present or is there but you are still having the name resolution error, create one and append the Google public DNS server as nameserver 8.8.8.8
Save the changes and restart the systemd-resolved service as shown.
$ sudo systemctl restart systemd-resolved.service
It’s also prudent to check the status of the resolver and ensure that it is active and running as expected:
$ sudo systemctl status systemd-resolved.service
2. Due to Firewall Restrictions
By some chance if the first solution did not work for you, firewall restrictions could be preventing you from successfully performing DNS queries. Check your firewall and confirm if port 53 (used for DNS – Domain Name Resolution ) and port 43 are open. If the ports are blocked, open them as follows:
For UFW firewall (Ubuntu / Debian and Mint)
To open ports 53 & 43 on the UFW firewall run the commands below:
$ sudo ufw allow 43/tcp
$ sudo ufw reload```
For firewalld (RHEL / CentOS / Fedora)
For Redhat based systems such as CentOS, invoke the commands below:
```$ sudo firewall-cmd --add-port=53/tcp --permanent
$ sudo firewall-cmd --add-port=43/tcp --permanent
$ sudo firewall-cmd --reload
I hope that you now have an idea about the ‘temporary failure in name resolution‘ error. I also found a similar git issue hope that helps
https://github.com/kubernetes/kubernetes/issues/6667
I want to export some data from MongoDB Atlas.
If I execute the command below, It tries connect localhost and export the data.
mongoexport --uri="mongodb+srv://<username>:<password>#name-of-project-x2lpw.mongodb.net/test" --collection users --out /tmp/testusers.json
Note: If you run this command from Windows CMD, it works fine
After researching the problem and with the help of a user, everything seems to point to a DNS problem and to the related resolv.conf file.
Below the original /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 "systemd-resolve --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
search name.com
At the beginning that resulted into a connection failure as shown below:
But if I would change that address into the following public available address according to what advised on this post to 1.1.1.1 the connection is successful, see below:
# 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 "systemd-resolve --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 1.1.1.1
options edns0
search name.com
Which resulted into a connection success as shown below:
HOWEVER the problem is that instead of explicitly connecting to the name of the MongoDB cluster, it will connect to the localhost, which is very strange as I successfully exported the files I was looking for from the real connection.
Which means that the machine was correctly connecting to the database but via localhost.
Everything seems to lead, also according to this source and also here to a DNS problem while connecting to MongoDB via terminal to export collections.
Now from this last post it not advisable to manually change this address for several reasons, therefore right after successfully exporting the data using DNS 1.1.1.1 I changed it back to its original DNS 127.0.0.53.
However I don't think this should be a proper behavior as every time I need to export data I will have to continuously and manually change this address.
What could be the reason for this strange behavior? And therefore what could be a long term solution without manually switching between DNS addresses?
Thanks for pointing to the right direction for solving this issue.
It seems you all ready have the answer in the links you mentioned. I will summarize this:
Install resolvconf (for Ubuntu apt install resolvconf), add the line nameserver 8.8.8.8 to /etc/resolvconf/resolv.conf.d/base, then run sudo resolvconf -u and to be sure service resolvconf restart.
To verify run systemd-resolve --status.
You should see on the first line your DNS server like here:
DNS Servers: 8.8.8.8
DNS Domain: sa-east-1.compute.internal
DNSSEC NTA: 10.in-addr.arpa
16.172.in-addr.arpa
This solution persists between reboots.
I am trying to install metasploit on crentos 6.6 server
now when i tried to yum install or wget or even git any bundle i got errors
then after alot of search i found that it is a problem in the DNS so i tried to edit /etc/resolv.conf
and add 8.8.8.8 as name server it worked fine but after server reboot or even eth0 restart it keeps returning without the modifications i made
this is my /etc/resolv.conf content
# No nameservers found; try putting DNS servers into your
# ifcfg files in /etc/sysconfig/network-scripts like so:
# DNS1=xxx.xxx.xxx.xxx
# DNS2=xxx.xxx.xxx.xxx
# DOMAIN=lab.foo.com bar.foo.com
is there any solution for this problem
I remember I got similar errors with CentOS.
Problem was: No internet connection.
First check a network connection:
#ping google.com
If there is no connection. You have to debug this first.
You are getting your networking configuration from DHCP but your DHCP server is failing to give you any DNS server addresses.
Did you try doing what that file tells you to do? Because that will "fix" your problem for you (assuming you don't choose to get your DHCP server fixed to provide you with DNS servers correctly).
Check location /etc/yum.repos.d/mongodb-org-3.2.repo
Delete all the irrelevent repositories in that location but be careful at that. Ex:- delete datastax repo which may be present
Run yum clean all
Run yum update
I have a Pi that runs hostapd and dhcpd on arch linux to create it's own land with the Pi's (routers) IP being 10.0.0.1. This uses the wlan0 interface and it only serves as a standalone router running a web server.
Once I connect to the Pi, I use 10.0.0.1 to display the web pages, but I want to use a hostname such as firepi. I have tried using dnsmasq, but I haven't been successful. Any help would be greatly appreciated especially if you can give me some detailed examples as I am a novice.
The purpose of this system is that I have created a web app that you can use to ignite fireworks over WiFi at a safe distance. I would just like the convenience of using a hostname instead of the IP address.
I must add that I will more than likely be using an iPhone to connect to the server, should this affect anything.
Not too sure how or why but this is what I did and it is successfully working now, so this is just for future users who may need a similar setup to mine.
First I installed hostapd and dhcpd and made sure they were working. Next I changed '/etc/hostname' to firepi and the '/etc/hosts' and added '10.0.0.1 firepi'. Then I installed dnsmasq, and set the interface to wlan0, and finally added '10.0.0.1 firepi' to '/etc/resolv.conf'.
After a full reboot, I joined the network on my iPhone, navigated to firepi and sure enough, it worked!
Thanks to the other users for their advice and tips.
You can use avahi on Arch as well to resolve your hostname:
sudo pacman -S avahi nss-mdns
Start the avahi daemon:
sudo systemctl enable avahi-daemon.service
sudo systemctl start avahi-daemon.service
Edit /etc/nsswitch.conf
sudo vim /etc/nsswitch.conf
Change the line:
hosts: files myhostname dns
to
hosts: files myhostname mdns_minimal [NOTFOUND=return] dns
Reboot
Note: don't forget to add .local to your hostname.
See also:
http://blog.pixxis.be/post/77285636682/resolve-hostname-with-arch-linux-on-a-raspberry-pi
If you just want to be able to use "firepi" as hostname to connect to it, you can simply add it to your /etc/hosts file using the syntax "IP host".
To make it as easy as possible, run this command as root:
echo "10.0.0.1 firepi" >> /etc/hosts
That'll do the trick.
Can you try avahi ?
sudo apt-get install avahi-daemon and
sudo apt-get install avahi-browse
I've successfully used that on Raspian. Unless you change the hostname using
sudo raspi-config you will access via raspberrypi.local
Note that if you plan to access the RPi from Windows you will need to install Bonjour Service first(if you have iTunes intalled, you might have those, run services.msc and check if the Bonjour Service is started)
Another note: On a friend's iphone I've installed a generic vnc client and had x11vnc running on the RPi and succesfully managed to connect to the RPi (since avahi-daemon was installed)