Questions tagged [linux]
Linux is the generic term for a UNIX-like open source operating system based on the Linux kernel.
38,337
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Roundcube imap domain
I have configuration Postfix+dovecot+roundcube. I have installed certificate SSL on domain main.example.com so when I have added below imap configuration test is ok and roundcube works. enter image ...
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Nvidia-smi missing GPU with SR-IOV disable in bios
I have a HPE serveur (DL385) with 3 Nvidia A100 in it. It is running ubuntu 22.04 with kernel version 6 (I have tried with the 5).
By default, it was in energy saving mode in the BIOS.
When I tried to ...
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Linux ubuntu: Determine what service/program is blocking ports
I have inherited a strangely setup server running ubuntu 22.04 and I cannot figure out what is blocking ports. iptables show nothing - just Chain Input policy accept. There is no ufw or firewall of ...
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Unable to get my rsync of my software RAID 6 past 40MB/s. Looking for suggestions
Wondering what I could adjust to get my RAID 6 Software Raid to resync quicker. Currently it's proceeding at max of 64MB/s and averages to something around 25MB/s. Hoping to get it to 200MB:
[...
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what effects performance of a tun/tap or a virtual network interface?
I know what a tun/tap device does in linux.
if I create a new tun interface with only a name and assigning an IP address to it, and leave other settings as default, like this:
sudo tunctl -t tun0
sudo ...
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SSH prompts with wrong host key/fingerprint
Using SSH to connect to a server (running Oracle Linux 7.9) I have set up, and I wanted to replace the original key pair I used with a different one. I am able to connect to the server using the new ...
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Change remote ssh download server location on another disk
My Visual Studio Code was installed on my main driver - Local Disk (C:) and has also installed the remote ssh extension. However, local disk c is already full and there's no space anymore. I can't ...
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How to change the batch size of pcp in linux kernel?
I increased the pcp->high via echo 8 > /proc/sys/vm/percpu_pagelist_fraction command, but the pcp->batch value still remains at 63.
vm stats threshold: 125
cpu: 383
count: 103931
...
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Iptables blocking https/http
Have boring problem, my php admin not accesible when iptables runing. Rules:
# iptables -L -v -n | more
Chain INPUT (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target prot opt in out ...
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Routing VM with two IPs in the same subnet
I have two NICs with IPs in the same subnet.
IP1: 10.10.10.142 - Gateway: 10.10.10.129 - dev: ens192.
IP2: 10.10.10.143 - Gateway: 10.10.10.129 - dev: ens256.
I want to configure static route to the ...
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Maximize duplicity efficiency
I'm creating incremental backups for a database. The size is around 8 GB per dump.
I have a backup creation policy, that looks like this: (don't worry, I already avoided collisions)
An increment ...
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28
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sudo with Kerberos credentials
We are on Oracle Linux 7.9, which is part of a Kerberos realm.
I would like account foo to be able to execute (without any password) one command as account bar with Kerberos credentials of bar ...
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Unable to ssh into remote server, despite port open and server reachable [closed]
As the title says, I am trying to create a home Linux server, and everything was going fine, including when I ssh into the server over LAN from both my laptop and my desktop.
I am a total beginner ...
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WireGuard portforwarding setup
I need help with the following scenario:
I have a small instance on AWS, which should accept all traffic from ports 1024:65535 and should send it to my local server. The local server shouldn't send ...
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How to allow kubernetes/calico traffic through iptables?
I have installed kubespray on my host. I want to close all ports on my host except the required ports. I want to add these rules:
iptables -A INPUT -p tcp -m multiport --dports 22,80,443 -j ACCEPT
...
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Samba Linux server MacOS client ACLs
I'm trying to enable ACLs for a Linux Server using a MacOS client.
My configuration is as follows:
[global]
vfs objects = acl_xattr
map acl inherit = yes
store dos attributes = ...
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Why do I have a large swapfile2 on my system?
I'm running a Digital Ocean Droplet running Debian 11 with 2Gb of memory, and there is a file /swapfile2 that is 6Gb in size, but I don't understand why it's there.
There is a /swapfile that is is 2Gb ...
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How can nft block excessive 443 access?
I'm having a hard time configuring nft to fight floods on 443/TCP.
I gave up on iptables and module recent, and now I'm testing nft with its man page sample code, as a lab.
So, I'm sending all source ...
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How can I add my workers to my Kubernetes cluster I created with kubeadm?
I have three VMS I created with vagrant that can communicate with each other. Following through a video and also K8s official documentation on creating a cluster with kubeadmn. The master node has ...
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how to create a new VG group on an installed Ubuntu Server 20.04
To give some context, I'm currently working on CIS Benchmark Hardening on the Ubuntu 20.04 on one of our product and I'm stuck on how to create a new vg group.
I have followed multiple way to do it ...
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Allowing packets from a different network to pass through
I have an internal network on 192.168.0.0/16. I would like for packets from the 10.0.0.0/8 network (Server 1) to pass through this internal network in order to reach the 10.0.0.0/8 network (Server 3) ...
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run windows server and centos on the same server [closed]
I’m currently working in a company where we need to run CentOS for our ERP system and a Windows Server system to manage employee PCs with Active Directory. We only have one server available. Could you ...
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Linux TCP tuning to overcome choking uplink
A linux computer is on a network link which exhibits the following behaviour:
good download speeds
upload/uplink starts well but after a few seconds drops to close to nothing. The Send-Q and Recv-Q ...
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Rsyslog not writing any logs from Cisco network devices - all other remote syslog works fine
tcpdump confirms valid syslog is coming in from multiple remote systems - servers and Cisco network equipment.
OS is Linux RHEL 8.8
The servers all come in fine and write to disk, and are shown as ...
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Migrate from /etc/network/interfaces to netplan
I am trying to migrate from /etc/network/interfaces to netplan and network-manager setup.
I am "almost" there.
My current setup with /etc/network/interfaces is as follows:
auto lo
iface lo ...
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md0 mount comes read-only after some writing
So I got a RAID 6 array (monitored) and I mount it to my filesystem (/mnt/mounting_point for this example). After some writing, for example:
sudo fio --name=seqwrite --filename=/test/seqwrite.0.0 --rw=...
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In firewalld , added rule is active but unable to list
Added Rule in a CentOS Linux 7 Machine
[root@localhost ~]# sudo firewall-cmd --direct --add-rule ipv4 filter OUTPUT 0 -d 8.8.8.8/32 -j REJECT
success
Rule is working as expected
[root@localhost ~]# ...
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How do I install .NET system-wide on an arm64 Ubuntu server?
I'm trying to install .NET runtime 6.0.16 system-wide. I need multiple users on a server to be able to access this from PATH. Generally, Microsoft recommends to use apt to install .NET packages -- but ...
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simplest way to run a tool inside a users RDP session from linux using only the commandline
I tried evilwinrm which works well to use a remote shell but smh I cannot directl ylaunch a GUI app inside of a users session.
It would also be ok to use ssh serve ron the Wndows RDS server or ...
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Cannot passwd for root with nslcd and openldap on Debian 12
Fresh Debian 12 for lab (VM). I installed: slapd, phpldapadmin, nslcd, nscd and dependencies.
I have two local accounts: root and user1. Also I have only user1 POSIX-account on local LDAP server.
I ...
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How to remotely access Ubuntu Server via RDP through a web browser
While this isn’t required for what I’m doing. It would be pretty cool to achieve. Right now I can access my computer running Ubuntu Server remotely from any Windows PC via Xrdp.
I want to take this a ...
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How to identify possible impacts on Amazon Linux system after a package update without updating package [closed]
I need to update some packages to their latest version as they are vulnerable. Before I do, I need to know the impact (System crash, inconsistencies etc.) on the system without updating those packages....
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I'm trying to expose a folder size in Node exporter but messes up. any suggestions?
This wasn't the case for a few months but suddenly my Node exporter in the server service messed up.
Oct 02 10:13:01 nodefs01 node_exporter[117252]: time="2023-10-02T10:13:01Z" level=error ...
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Why are all communities unlinked? [migrated]
I examine questions on stackoverflow, stackexchange, and the subdomains for specializations. Every time I want to upvote or save a question or ask one on a new forum, I am prompted to make a new ...
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How to tune a lagging linux server? [duplicate]
A server is lagging a lot while viewing logs, even when I'm using less comman to view the logs. Yes, I agree the log sizes are worth 400MB (after splitting).
One of the issues I think could be the ...
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Debian 9 (Stretch) - Broken dependencies on a libc6 upgrade
Good morning,
I'm using Debian 9 (Stretch).
I was updating my php version using the repositories below:
#deb https://deb.debian.org/debian/ stable main contrib non-free
#deb-src https://deb.debian.org/...
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UFW firewall deny incoming connections except for one ip
I want to deny all incoming connections to port 6677 except for one ip-address (so it can only be reached from a docker container running on the host, the port should not be accessible from "...
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Connecting to MariaDB server: ERROR 2013 (HY000): Lost connection to server at 'handshake: reading initial communication packet', system error: 11
I am trying to connect to an AWS hosted (RDS) MariaDB database (engine version 10.6.14). The database is hosted on a private subnet but it's accessible through a bastion host. I use an SSH tunnel to ...
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Amazon Linux 2023 AMI Permissions
I'm setting up a new EC2 Instance with AMI Linux 2023. (I'm super new to Linux/AMI). I followed this tutorial on the AWS website: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-lamp-amazon-...
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serverside fetch request timeout when request are to an external domain which has the same IP as origin domain
I'm currently running a SvelteKit app within a container which connects to an API running within aother container. Everything is connecting & going through locally using the container's internal ...
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Newbie: How to add mod_sec rule exception for specific use-case
maybe someone with experience or basic knowledge that knows what they're doing (unlike me :)) can help....
Currently, I have Ubuntu 20.04 installation with OpenLitespeed and Cyberpanel.
I've installed ...
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Alma linux 8 update fails for any package with CPG keys check fail
I have upgraded a Centos7 server to Centos8 and then to Almalinux 8.8. If I run dnf update I get an error for any package. I have removed yum so I am using dnf. I have tried dnf clean all but the ...
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Can I copy the files in my original /opt directory after I mount a new LVM on the /opt?
I have new LVM on my Linux server and I want to mount on my /opt. I have files in the /opt directory and I know after I mount, the files will be hidden. Is it possible to rsync the files in the /opt ...
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interrupt all tcp/udp session in TUN interface or NAT
I have a vpn server in my linux machine and some people are connecting to that.
sometimes one of the users consumes half of the bandwidth at the time I need the resources.
I know internal ip of that ...
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is /etc/sudoers writable or not
The default permission in /etc/sudoers file is readonly for root and group root as in picture is obvious :
So when you open it with any test editor it can't be written and give error read only.
now ...
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Unable to configure fail2ban to protect samba shares
With this configuration service (fail2ban) starts, logfile register wrong attempts, but still not count attempts in fail2ban-client. I suspect that there is a problem with regex, but this is the only ...
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How does scsi multipath work?
I don't understand a little.
(hypothetical situation)
I have a Supermicro server with Linux. A pci hba is inserted into it. In the hba, via sff-8644, a jbod with 90 ssd is connected. sff-8644, this is ...
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Systemd service executing a script with error handling
I have the following issue:
I created a systemd service which executes a script. This script contains several commands including psql commands which queries a database and stores the outcome into ...
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Firewalld is not working,. port open but I can't reach from other server
I got a wildfly 9 server on REHEL 7 with ports http=4070. Then I executed the following instructions:
[root@linux]# firewall-cmd --add-port=4070/tcp --permanent
Warning: ALREADY_ENABLED: 4070:tcp
...
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Wireguard with multiple local subnets using iptables
I'm trying to allow multiple local subnets when using a wireguard VPN. Below is the iptables config from my wireguard config file.
I'm assuming I have to write this in a different way, but I have no ...
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