New answers tagged linux
0
votes
How to reset nftable counter?
I found 2 ways to reset anonymous counters.
Tested with kernel 5.15.0-121-generic and nftables 1.0.2-1ubuntu3 on Ubuntu 22.04.4. (May or may not work with vanilla kernel and nftables... maybe it's ...
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0
votes
How to disabling certain UDP service ports?
Use:
iptables -I INPUT -p udp --dport 111 -j DROP
or
iptables -I INPUT -p udp --dport 111 -j REJECT
Replace 111 with the port number you want to block.
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0
votes
How to prevent Avahi adding -2 to hostnames
On an RPi with console autologin, I added
sudo service avahi-daemon restart
at the end of .bashrc.
0
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socat forwarding to multiple addresses
I had the same use-case, I wanted multiple ports forwarded. I found this answer in another thread.
https://unix.stackexchange.com/a/751459
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0
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Service start request repeated too quickly, refusing to start limit
In my case, running Saltstack to install the package, copy files and start the service, the root cause was the configuration file for the service needing to have rw------- (0600) permissions.
I was ...
- 19
0
votes
How to force delete directory backed by Gluster that will not delete even when using -r option
In some cases, You won't have any other choice but to delete from the backend: meaning on each node then on each brick of the node.
glusterfs 5.5 on debian 10 (buster)
0
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Apache mod QOS is blocking all users when it should only block per IP
if you are using a reverse proxy, try using QS_ClientIpFromHeader X-Forwarded-For instead of remoteIP
<IfModule mod_qos.c>
QS_ClientIpFromHeader X-Forwarded-For
QS_ClientEventLimitCount ...
0
votes
Ansible: how to explain that sometimes $HOME environment variable is set and sometimes not?
No, lookups do not use the become system. So expressions like lookup('env') are run as the user running ansible-playbook. Actually, the only thing become can affect is modules, and they are run in ...
- 34.2k
0
votes
ssh hostname.local on LAN? Why does it work?
special use domain names are not resolved through the internet.
https://www.iana.org/assignments/special-use-domain-names/special-use-domain-names.xhtml
and "local" is one of these domain ...
- 131
0
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iostat - dm-0 device shows much higher latencies than sdX
Average request duration = Total request duration/Number of requests. In some cases, the number of requests is not calculated within several seconds. As a result, the denominator is too small and the ...
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0
votes
How to find the browser versions from command-line in Linux & Windows?
[ "$(google-chrome --version | grep -oP '\d+(.\d+)+')" != "$(curl -sSL https://dl.google.com/linux/chrome/deb/dists/stable/main/binary-amd64/Packages | grep -A 1 "Package: google-...
4
votes
Disable encryption on wireguard
Wireguard doesn't support plaintext tunnelling, its not meant to.
I think using a pubilc facing tunnel without securing the packets is not a sound idea.
I'd be very surprised if your latency ...
- 23.9k
2
votes
Accepted
Obtain a list of RPM packages to update a system
Based on this answer you can get the history of dnf executions with the commands
dnf history
then you select which of the history ID you want to see in details with command:
dnf history info <ID&...
- 6,312
0
votes
get notification when systemd-monitored service enters failed state
The OnFailure= service way is the most "systemd way" I think. Other ways:
ExecStopPost= will execute after the service is stopped, where you can then check $SERVICE_RESULT with bash.
...
- 111
1
vote
Steps to succesfully persistent iSCSI LUN using Open-iSCSI on Ubuntu Server?
All iSCSI is doing is presenting a block device, but it still needs to be formatted with a filesystem before it can be mounted. This has (2) parts:
a) Partitioning:
So in the output of fdisk -l find ...
- 415
1
vote
Accepted
Fresh rocky9 install causing PCI bus errors?
The workaround/solution for this is published by Red Hat: https://access.redhat.com/solutions/7062084
You can downgrade to kernel 5.14.0-284.11.1.el9_2
Or you can add the following parameter to the ...
- 199k
1
vote
where is the updatedb database located?
The most advanced variant of locate today is plocate and its DB is usually stored at
/var/lib/plocate/plocate.db
plocate is used at least by Fedora and openSUSE Tumbleweed as a default locate program....
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2
votes
Accepted
COW filesystems (BTRFS, ZFS, bcachefs) scrubbing and RAID1 with mdadm on Linux
Yes, when running on top of mdadm the ZFS, etc. scrub can not correct corruption that happend to the individual disks. That is one of the main reasons why those filesystems strongly prefer direct ...
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1
vote
Run a shell script as a different user
For sites that may have special PAM setups that make this difficult, you can bypass su/sudo entirely with systemd and a little more typing:
Define a oneshot service that executes your script. If your ...
- 11
2
votes
CLI tool to monitor file size growth, transfer rate, and calculate progress bar/ETA?
You can do this relatively easily using tqdm. Something like this seems to do what you want, assuming that you know the expected size of the target file in advance:
# expected total file size in bytes
...
- 46k
2
votes
Poor network bandwidth on a point to point connection between 2 linux machines with Mellanox ConnectX-6 cards
server grade rackmount systems - what are those systems and specifically which slot have you plugged the NIC in?
The MT28908 ConnectX-6 supports PCIe 4.0 x16 with a theoretical bandwidth of up to 252 ...
- 12.6k
0
votes
How to add youtube into ip rule list?
You can perform DNS lookups to get the current IP addresses for YouTube:
Using dig:
dig +short A youtube.com
This command will return the A records (IPv4 addresses) for youtube.com.
Using nslookup:
...
- 11
1
vote
ssh blank passphrase but still asking for it
A trailing space after END OPENSSH PRIVATE KEY----- causes openssh to treat the ssh key as encrypted and just hitting enter at the prompt doesn't work. I verified this on RH 7.9 and openssh_7.4p1 ...
- 11
0
votes
How to change the text of Emails sent by sudo via mail_badpass?
It's always a good idea to start by reading the manual - and specifically the manual already installed on your machine. That way you know you're getting the right documentation for the right version ...
- 23.2k
0
votes
How to add a timestamp to bash script log?
The best way for me is to define a function echo_ts and use it in my script instead of the built-in echo command:
echo_ts() {
local timestamp=$(date +"%Y-%m-%d %T")
echo "[$...
- 101
0
votes
Allowing and restricting access to specific URL in Apache 2.4
More generally I'd go for the Location bit since /var/www/html/ does not contain necessarily contain the published url files:
<Location /admin>
Require ip 1.2.3.4
</Location&...
- 101
0
votes
Connect two networks over a VPN connection linux
The important bit was that I was using Wireguard, so adding the subnets to allowedIPs in the WG client configs and the appropriate routes was all that was needed.
1
vote
Accepted
How to modify /etc/hosts file for root domain in a vps server?
Your domain changes are okay, but even if you intend to put a whole FQDN in /etc/hostname, you should still make sure that the short hostname (i.e. just the first component, example in your case) also ...
- 12.5k
0
votes
Manage VLANs on Linux Bridge and KVM host
After a lot of attempts, seems like linux bridges can't do what i want with KVM. The only "solution" I have found is the following:
bond1 -> bridge data ( vlan-filtering1 ) -> veth (...
- 19
1
vote
Connect two networks over a VPN connection linux
There are no specific iptables rules for connecting networks. Iptables doesn't do routing – it does filtering, whereas your routing table does routing – so the only iptables rules you may need are ...
- 12.5k
0
votes
Manage VLANs on Linux Bridge and KVM host
Avoiding the additional bridges is possible when utilizing MacVTap:
Switch - tagged port -> Linux physical interfaces -> Linux bond interface -> Linux VLAN interfaces -> Linux MacVTap ...
- 1
5
votes
Allow ssh-rsa with OpenSSH 8.7
ssh-rsa is not a key-exchange algorithm.
The two lines in your error message are not related to each other – they report two different cases of unsupported algorithm in different categories.
Diffie-...
- 12.5k
0
votes
DH GEX group out of range
This is a problem with the chosen key exchange method. You need to manually set a compatible one.
Disabling all key exchange methods on the client will show what the server offers:
ssh -o ...
- 71
1
vote
Linux e1000e (Intel networking driver) problems galore, where do I start?
I had the same problem while trying to create my specialized Kernel 6.10.6 configuration for my ThinkCentre M70q.
The problem was related to setting CONFIG_PCIE_ASPM_PERFORMANCE instead of ...
0
votes
Symbolic link of all files in a folder to an existing folder
Linking folder A to a subdirectory in an existing folder B seems the most logical.
ln -s A B/sub
If you do need to link files to an existing folder, you can link them one at a time. However, this ...
- 1
0
votes
Why doesn't my one-to-many ip6gre tunnel work?
This is due to a bug in Linux. In ip6gre_tunnel_xmit one of the first checks called is ip6_tnl_xmit_ctl to validate the source and destination address. However, it only validates the source and ...
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0
votes
How to set permission so that `du` can be run as some user on external drive directories that are owned by multiple other users?
However, I think the issue would remain when new users (in other containers/VMs) create new files - they would again need to be chmod
Define ACLs using setfacl. You can add multiple users or groups ...
- 12.5k
0
votes
How to get x86_energy_perf_policy // linux-tools-* for Linux kernel 4.7.0-xyz
In recent releases x86_energy_perf_policy is provided by linux-cpupower package:
apt install linux-cpupower
See man page.
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0
votes
"docker: 'compose' is not a docker command." How to use the alias "docker compose"?
Try with:
sudo apt install docker-compose-v2
Tested in Ubuntu 22.04.
0
votes
nsupdate answering SERVFAIL
I had the same issue but my zones file was somewhere else
sudo chown -R bind:bind /var/lib/bind
0
votes
How to install company proxy certificate
For me downloading the relevant certificates worked nicely with
host=www.apache.org; \
echo "" | openssl s_client -showcerts -connect ${host}:443 | \
awk '/-----BEGIN CERTIFICATE-----/ { i++;...
1
vote
What is inside /var/lib/nginx/body, it's size is more than 40GBs for me and it keeps on increasing
On Debian (and presumably other Debian-derived distributions such as Ubuntu), this directory corresponds to the --http-client-body-temp-path= build configure option, which is hardcoded in the Debian ...
- 2,242
0
votes
tar - Remove leading directory components on extraction
When extracting one item from the archive, --strip-components=NUMBER option can be used. However when extracting more than one item, --transform is helpful. E.g.
tar xf archpackage.tar --transform=&...
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0
votes
In RHEL how does one set a default global DNS server using systemd NetworkManager instead of on a per nmcli connection basis?
Did you check the Red Hat Enterprise Linux documentation? It has an entire chapter covering this.
Chapter 21. Manually configuring the /etc/resolv.conf file
By default, NetworkManager dynamically ...
- 51k
0
votes
Nginx displaying failed (13: Permission denied) when trying to access new site
This is not common to all but this can be the one scenario
I also faced such issue with Harden Ubuntu 22.04 VM where the umask was set to 077 i.e for group and others don't have any permission. And ...
0
votes
Slow performance copying large file over network (scp)
I think that to speed up transfer using your 802.11g wireless connection, you shoud multithread the transfer of the 300Gb file.
Since 2023 and need for different scientists research groups to ...
- 11
0
votes
Linux - Formating multiple-pattern-select with grep
You can use Perl to remove the newlines from every odd line:
... | perl -pe 'chomp if $. % 2'
-p process the input line by line and prints each line after processing;
chomp removes the final newline (...
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0
votes
Accepted
SSSD failing to start
We were able to solve the SSSD connection errror.
These are the steps that we did to solve it.
In /etc/sssd/sssd.conf , change enumerate from false to true.
enumerate = True
Remove the files mentioned ...
0
votes
How to add a timestamp to bash script log?
It worked for me
#!/bin/sh
DATETIME=`date "+%Y-%m-%d %H:%M:%S"`
echo "[$DATETIME] TYPE_YOUR_MESSAGE" >> output_file.log
Output Log File: output_file.log
[2024-08-22 14:13:...
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0
votes
Accepted
Ubuntu Samba share for Windows and Mac
After sitting down recently to finally figure this issue out, it turned out the solution was unfortunately, quite simply, to just update the Samba client. I guess something changed in Samba 4.8 ...
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