Questions tagged [linux]
Linux is the generic term for a UNIX-like open source operating system based on the Linux kernel.
38,089
questions
-1
votes
0
answers
18
views
What dose this iptables command do? [closed]
could you please help me:
What does this Linux iptables command will do?
Iptables –A INPUT –P Udp –Dport 53 –J DROP
0
votes
0
answers
11
views
Why isn't my zpool listed for export when plugged into new host?
I have a zpool called 'temp' with some data I'm trying to move between systems. I used zpool export temp to export the zpool, then I unplugged the disks, and installed them in my new computer. But now ...
- 333
0
votes
0
answers
14
views
Ngninx "cannot load certificate BIO_new_file() failed (SSL: error:0200100D:system library:fopen:Permission", help fix this [emerg] error
I am running an Ubuntu 20.04 LEMP server on a Raspberry Pi 4. In my nginx errror logs I am getting the following error:
2023/05/29 11:51:40 [emerg] 3356#3356: cannot load certificate "/etc/...
- 93
0
votes
0
answers
14
views
Mounting an encrypted fs WITH prompt at boot time (LUKS, cryptsetup)
Per company policy my laptop has to be very secure in case of theft, so I have created an encrypted partition (LUKS) that I want to mount via /etc/fstab.
However, I do NOT want to add passphrase to ...
- 1,311
-1
votes
0
answers
21
views
Need a tool that can save and run the docker images in non-internet machines [closed]
I am currently working on a project which needs to be deployed on customer infra (which is not cloud) and also it will not have internet.
Please provide some options where we can save all the ...
0
votes
0
answers
16
views
Can't pull a docker image on Cent OS server, but works fine on local Ubuntu OS
This command fails on a CentOS server but succeeds on an Ubuntu based laptop:
# server, CentOS based
$ docker pull jwilder/nginx-proxy:latest
Error response from daemon: manifest for jwilder/nginx-...
- 908
0
votes
1
answer
34
views
IPTABLES no internet access from lan with default FORWARD rule set to DROP
I'm trying to set up ubuntu server 22.04 (virtualized) as a router with one wan interface (ens18) and several lan interfaces ens19:ens23 & ens1.
Here is what im trying to achieve:
allow ens19:...
-1
votes
0
answers
25
views
Develop program that do not blindly accept package from anyone except selected IP [closed]
I used Socket programming in python3 but the problem is that other public computers know about the open port information. whether port 12345 is open or not. I want some low-level programming which not ...
- 1
0
votes
0
answers
16
views
Number of receiving queues is double the number of cores of my server?
I'm using Mellanox ConnectX-5 100 GB NIC, Linux kernel 5.15 and my server has 32 cores (SMT disabled). But in the /sys/net//queues, the number of rx queues is 64, which is double the number of cores ...
- 1
0
votes
0
answers
5
views
Specific olcAccess does not work for an OU in LDAP
On my OpenLDAP server, I would like the accounts in my "ou=partners" OU to have "read" permissions to all objects in "ou=abos". Here is the tree of my DIT :
[ditTree][1]
...
0
votes
1
answer
26
views
Postfix: Can't send mails from another network
I recently set a postfix (+dovecot) mail server (on a VPS) and when I am in my own home network, which I put in mynetworks, I can both send and receive mails.
However when I am outside home I can only ...
- 11
0
votes
0
answers
12
views
ipsec package after decrypted can not be recieved by tproxy
My centos6 machine ipaddress is 192.168.56.10 (eth0). I have installed strongswan and a tproxy like v2ray with iptables:
iptables:
*mangle
:PREROUTING ACCEPT [0:0]
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [...
- 1
0
votes
0
answers
26
views
How to use one ip as a proxy to reach another ip in linux? [closed]
I have two linux machines A abd B with IPs 172.31.9.10 and 172.31.9.11. I have docker running in A, and the IP of one of the containers is 172.31.8.9.
In short, 172.31.9.10 can be reached from 172.31....
- 111
-1
votes
1
answer
17
views
Domain user directory being created as /home/username@domain instead of /home/username
I am using an amazon linux 2023 box and i joined the instance to domain using realmd.
The issue is that when i try to login with my AD credentials, the user directory is being created as /home/...
- 115
0
votes
0
answers
51
views
LVM disk is corrupt - is any data recoverable?
Under RHEL7 we have a logical volume consisting of 27 volume groups PVs. Each of these VGsPVs was added sequentially as we ran out of space on the LV.
We do not have a backup of the data. There are ...
- 141
-1
votes
0
answers
20
views
Effective computational resource management for a server shared by multiple users [closed]
What would be the optimal approach to effectively manage and restrict CPU and memory resources on a server utilized by a group of approximately 50 users? The server in question is a single-system-...
- 31
0
votes
0
answers
16
views
Samba share suddenly stopped showing on Windows
I have 20 computers in my office network and all the computers run windows10 except one which is running Ubuntu. I have setup a samba share on that machine so that others can access the share drive ...
- 101
0
votes
0
answers
15
views
BIND 9 XML Statistics-channels build modification after server is already up and running
Migrating away from BIND to R53 and would prefer not to use the named.stats file for monitoring activity during the migration period. As such, I checked the current named.conf and verified no ...
0
votes
1
answer
28
views
ntpdate works but ntpd servers stuck at .INIT
There have been several similar questions to this, but none with resolutions.
I can run ntpdate on the machine, and the date is updated. I assume that this means there is no firewall problem.
I have ...
- 123
0
votes
0
answers
24
views
Double proxy for web browsing [closed]
Im facing this setup:
Computer1 (Linux) with VPN and additional proxy configuration (single proxy address for single domain) for web browsing internal services
and Computer2 (Windows).
I want to be ...
0
votes
0
answers
28
views
What is the best practice for servers - EFI or legacy mode?
I'm currently installing a new Linux server and am trying to decide whether to use legacy mode (BIOS) or EFI. So far, I'm leaning towards legacy because it's less complex (less partitions) and has ...
- 221
0
votes
0
answers
16
views
Saving contents of /proc/net
I'm trying to archive files from /proc/net when a process crashes. This is to aid in debugging, to get understanding about the machine status when crash happened.
The contents are not regular files, ...
- 333
1
vote
1
answer
37
views
What is the INPUT_direct chain in firewalld?
In many firewalld config examples I see mention of the normal INPUT iptables chain, as well as one named INPUT_direct.
e.g.
$ sudo firewall-cmd --direct --add-rule ipv4 filter INPUT_direct 0 \
# etc....
- 851
0
votes
1
answer
15
views
How to extend root volume / with an extra storage disk
I am trying to add a 2nd disk to a CentOS 8 instance and I want to extend the entire storage utilizing all the available extra space;
1st storage: 40 GB
2nd storage: 100 GB (added later)
The problem ...
- 113
1
vote
1
answer
47
views
How does one set ownership of a directory using nfs4_setfacl?
Or put another way, when I see @OWNER in a nfs4 ACL does this @OWNER refer to a local Unix/Linux user?
I need to make an AD user (without a corresponding local account) the owner of a directory on a ...
- 911
-1
votes
1
answer
47
views
How do I set up a godaddy hosting server
A client has contacted me, requesting to deploy a custom solution (python API and a react application) to his GoDaddy server.
I successfully established SSH connection (which was hell, I had to enable ...
0
votes
0
answers
21
views
Fortify SCA, Translation daemon appears to be stuck. Killing <pid>
Currently trying to perform a scan on a large C/C++ code base using gcc in Linux and "Translation daemon appears to be stuck. Killing " issues are occurring often throughout the translate ...
- 1
1
vote
1
answer
28
views
Forward port to a VM via iptables from same bridge
I have running a proxmox server with two VMs which are connected to the bridge interface vmbr0:
Host: 10.10.10.1 (extern IP: 123.123.123.123)
VM1: 10.10.10.2
VM2: 10.10.10.3
On VM2 a load balancer ...
- 107
-1
votes
0
answers
31
views
Cannot kill -9 Trend Micro Deep Security Agent
My company has deployed Trend Micro Deep Security on our RHEL server per regulation.
The usual way to enable/disable the agent is through Deep Security's management console.
However I am tasked with ...
- 5,006
0
votes
1
answer
25
views
Logging of "direct" iptables rules with firewalld
I'm using firewalld with the iptables backend. I added "direct" rules for ssh connection limiting:
sudo firewall-cmd --add-port=22/tcp
sudo firewall-cmd --direct --add-rule ipv4 filter ...
- 851
0
votes
1
answer
47
views
Testing rate limiting rules in firewalld
I want to rate limit ssh connections per IP to a server running firewalld.
Suppose my sshd listens on port 2222, and I want to limit ssh connections per IP to 3 per minute. I tried:
sudo firewall-cmd -...
- 851
0
votes
1
answer
39
views
KVM - Reduce Storage Size of QCOW2 File To Specific Size
I want to reduce the storage size of the VM's running on a Linux 8 physical machine from 2 TB to 400 GB. The actual size of VM's is around 100 GB. But the space we give it as allocated size is too big ...
-1
votes
0
answers
42
views
TC limit Speed with Multiple Ports [closed]
i have an script that works well for single port limitation writen in bash and works with TC
but imagine each vpn users connects to server with unique port, how can we set speed limit each ?
exp: ...
- 1
-1
votes
1
answer
58
views
Cannot delete files from /home folder in centos7 [closed]
I am trying to delete a file inside /home folder as root user but i am getting error "Operation not permitted". Below is the lsattr of file
-----a-------e-- /home/test/.bash_profile
also if ...
- 21
0
votes
1
answer
18
views
Linux Hostname - SystemD Service File Causing NetworkManager to Fail on Boot
systemd[1]: NetworkManager-wait-online.service: Job nis-domainname.service/start deleted to break ordering cycle starting with NetworkManager-wait-online.service/start
- 101
0
votes
0
answers
20
views
PROMPT_COMMAND duplicating commands on new sessions
Im playing around with PROMPT_COMMAND variable
Was testing out some ways to save all commands into a log file and got some ways using PROMPT_COMMAND + logger + rsyslog
Example export im using
export ...
- 23
0
votes
0
answers
85
views
What could be the reason that `apt update` says certificate is NOT trusted whereas curl says `SSL certificate verify ok`
I am trying to add docker to my Debian 11 bullseye installation.
until now, I have ran -
apt clean
apt update
update-ca-certificates
apt-get install -y ca-certificates
apt reinstall ca-certificates
...
- 111
0
votes
0
answers
34
views
stress-ng: Simulate specific CPU and Memory Percentage
Goal : For performance test I m using stress-ng and I want to consume 100% CPU of 3 out of 4 Core and 80% of entire memory for 30 min (this is very extreme test condition). And I have few other ...
0
votes
0
answers
9
views
Cwd of a process started from hard link path
I have an app which is starting by path which contains a folder which is hard link.
If I look for process current working directory it is same as source of a hard link.
The main problem is that app ...
- 101
0
votes
1
answer
26
views
How is php-fpm socket folder ({/var,}/run/php-fpm) created on Linux?
I am setting up multiple php versions on CentOS7 (native and from remi repos). As installed, the native php-fpm ( is setup on a unix socket, while the (remi) php74-php-fpm would listen on a TCP socket....
- 2,299
0
votes
1
answer
18
views
Migrating server and backup server to bigger RAID 1 (software) arrays
I have 2 boxes. The server (actually an ownCloud server) and a backup server. Both are running Ubuntu servers.
The main server has a RAID 1 array of 2x2TB drives.
The backup server has a RAID 1 ...
- 331
-1
votes
0
answers
21
views
Moving databeses and applications to containers
I have production server let's call it SERVER1. Structure looks like this.
SERVER1 -- bare metal
Debian11
Apache2 with proxy_https
Database server mariadb
Databases:app1,app2,app3, app4
Directory &...
- 1
1
vote
2
answers
30
views
Delete folders asynchronously
I have a large file system in which I have to delete certain directories from time to time. Currently I have a script which amongst other things, deletes a folder and subsequently generates an email ...
- 232
0
votes
1
answer
33
views
Can you force replacement of files marked %config in RPMs
If files in RPMs are marked %config or %config(noreplace)¹, running something like dnf update or yum update will not touch (modified) configuration files, but leave the old ones in place and create ....
- 101
0
votes
0
answers
18
views
How to remove msdos parition table label completely on Rocky Linux 8.7 [duplicate]
How to remove msdos partitions on Rocky Linux 8.7, while the command fdisk -l provides no partition table label, the command partprobe shows msdos label, which I want to remove
# fdisk -l /dev/nvme0n1
...
0
votes
1
answer
28
views
Disabling password authentication
Suppose I want to allow SSH authentication only, and disable password authentication.
In /etc/ssh/sshd_config I've typically done this:
PasswordAuthentication no
But in some answers people recommend ...
- 851
0
votes
0
answers
27
views
NetFilter ConnTrack FTP helper alernative fo handle FTPS
I've been using nf_conntrack_ftp module successfully (though rarely), but now I have to deal with TLS-encrypted FTP - this renders that helper useless an I would have to resort to opening the firewall ...
- 198
0
votes
0
answers
19
views
performance issue when linux(ubuntu) work as router with ip_forwarding enable
I'm running a test with this topo: tester---(port1)ubuntu_linux(port2)----tester. I enabled ip_forwarding in ubuntu_linux by : echo 1 > /proc/sys/net/ipv4/ip_forward
The tester is trying to find ...
- 1
0
votes
1
answer
35
views
umount of logical volume failing during shutdown
In my system, multiple logical volumes are created, mounted and /etc/fstab entries are added after systemd starts up.
When system is rebooted for the first time, during shutdown many umount failures ...
- 333
0
votes
1
answer
70
views
IPv6 to IPv4 converting - tunnel between to ubuntu servers
I live in a country that recently launched a heavy censorship protocol on Internet.
most of the IPv4s are restricted or completely banned.
I have two servers , one in my country and another one in ...
