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ssh: Could not resolve hostname ... Temporary failure in name resolution (Ubuntu 22.04)

cn flag

Please help me figure out what the problem is and how to fix it. I'm using Ubuntu 22.04.

The problem is that when I try to clone the repository

~ git clone git@bitbucket.org:some_user/some_rep.git
Cloning into 'some_rep'...
ssh: Could not resolve hostname bitbucket.org.somehost.local.: Temporary failure in name resolution
ssh: Could not resolve hostname bitbucket.org.sh-dev.local.: Temporary failure in name resolution
Receiving objects: 100% (23/23), 8.21 KiB | 8.21 MiB/s, done.
Resolving deltas: 100% (8/8), done

I am getting warnings Could not resolve hostname. As far as I understand, this is due to dns search domains .somehost.local and .sh-dev.local appended to host while doing dns resolving.

These are the search domains of my former employer and they are no longer needed. I can't figure out where they are managed and how to get rid of them.

~ grep hosts /etc/nsswitch.conf
hosts:          files mdns4_minimal [NOTFOUND=return] dns

~ clone nmcli connection show
NAME                           UUID                                  TYPE      DEVICE
myWifiName                     b81dd4e6-1bd3-4659-8a36-713bfe1fd7aa  wifi      wlp0s20f3
br-ce3f272b0bd1                8e917327-20e3-419d-8b2e-a22e86cbdc83  bridge    br-ce3f272b0bd1
br-e3bb71106bfa                d10a83ad-bb4e-4fed-88b9-15e8ac1a9483  bridge    br-e3bb71106bfa
docker0                        dfa05eee-2bae-4c49-afd8-7f5b5de0cdeb  bridge    docker0
enp0s31f6                      54ec474d-eb2a-4eea-8f29-8f25fe325210  ethernet  enp0s31f6
office_vpn                     7eea950c-a520-423a-8804-9d1907f590ca  vpn       --
Wired connection 1             e2683831-e13a-3dd5-9db4-4f414fad75bf  ethernet  --

~  nmcli con show myWifiName | grep ipv4.dns
ipv4.dns:                               --
ipv4.dns-search:                        --
ipv4.dns-options:                       --
ipv4.dns-priority:                      0

~ sudo lsof -i :53                                    
COMMAND     PID            USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
systemd-r 23016 systemd-resolve   13u  IPv4 164764      0t0  UDP localhost:domain 
systemd-r 23016 systemd-resolve   14u  IPv4 164765      0t0  TCP localhost:domain (LISTEN)


cat /etc/resolv.conf 
# This is /run/systemd/resolve/stub-resolv.conf managed by man:systemd-resolved(8).
# Do not edit.
# blah-blah-blah ....

nameserver 127.0.0.53
options edns0 trust-ad
search .

UPDATE: I figured out some more: These search domains are injected by networkmanager when i turn on vpn nmcli con up myVPN systemd-resolved[45936]: tun0: Bus client set search domain list to: somehost.local, sh-dev.local event is logged

~ sudo resolvectl domain  
Global:
Link 2 (wwan0):
Link 3 (enp0s31f6):
Link 4 (wlp0s20f3):
Link 5 (br-ce3f272b0bd1):
Link 6 (br-e3bb71106bfa):
Link 7 (docker0):
Link 15 (tun0): sj-dev.local sj-dev.ru

When i turn off vpn with nmcli con down myVPN systemd-resolved[45936]: tun0: Bus client reset search domain list. event is logged and

~ sudo resolvectl domain 
Global:
Link 2 (wwan0):
Link 3 (enp0s31f6):
Link 4 (wlp0s20f3):
Link 5 (br-ce3f272b0bd1):
Link 6 (br-e3bb71106bfa):
Link 7 (docker0):

But somehow these dns search domains are still being used when resolving domains. What could be the reason and how to fix it?

UPDATE2: Problem was in ~/.ssh/config deleting this option resolved the problem

Host *
   CanonicalDomains  ...
David avatar
cn flag
The keyword in the error is temporary. At this second what ever the DNS server you are sending requests too can not process them. Two things you can do wait a bit and try again or use a different DNS server. You may want to change the title of the question to ask what is the real issue. How to change the DNS configuration. This is what you are saying further down in your question.
not null avatar
cn flag
Changed the title. I think the error is related to how dns search domains work: first they resolver tries to resolve host under these search domains and if fails then outside of these domains. I do not understand where these domains are recorded and how to change or delete them.
David avatar
cn flag
Not sure what it is you did with the title but here is a title that matches the info in the question and add nothing more to the title. How to change the DNS configuration. This will tell anyone who might be able to help what your actual issue is.
not null avatar
cn flag
thank you for help, changed again
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