Questions tagged [linux]
Linux is the generic term for a UNIX-like open source operating system based on the Linux kernel.
38,421
questions
0
votes
0
answers
23
views
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
...
- 139
0
votes
2
answers
74
views
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 ...
0
votes
1
answer
91
views
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 ...
- 11
0
votes
0
answers
52
views
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 ...
0
votes
1
answer
103
views
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 ...
- 173
0
votes
1
answer
64
views
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 ...
- 21
0
votes
1
answer
130
views
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
...
- 101
0
votes
0
answers
44
views
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 = ...
0
votes
0
answers
35
views
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 ...
- 101
0
votes
0
answers
41
views
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 ...
0
votes
0
answers
22
views
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 ...
0
votes
1
answer
83
views
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 ...
- 880
0
votes
1
answer
83
views
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 ...
0
votes
1
answer
181
views
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 ...
- 21
0
votes
0
answers
76
views
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=...
0
votes
0
answers
15
views
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 ~]# ...
- 115
1
vote
1
answer
62
views
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 ...
-1
votes
1
answer
60
views
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 ...
- 11
0
votes
1
answer
98
views
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 ...
- 21
-1
votes
4
answers
391
views
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 ...
0
votes
0
answers
76
views
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 ...
0
votes
0
answers
28
views
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 ...
- 124
0
votes
1
answer
104
views
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 "...
- 3
1
vote
0
answers
325
views
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 ...
- 111
0
votes
0
answers
105
views
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-...
- 101
0
votes
0
answers
110
views
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 ...
0
votes
0
answers
24
views
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 ...
0
votes
0
answers
157
views
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 ...
- 111
0
votes
2
answers
46
views
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 ...
- 1
0
votes
1
answer
82
views
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 ...
- 172
0
votes
1
answer
104
views
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 ...
- 1
1
vote
0
answers
34
views
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 ...
- 11
0
votes
0
answers
106
views
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 ...
- 1
0
votes
1
answer
86
views
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
...
- 165
0
votes
1
answer
107
views
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 ...
- 1
0
votes
1
answer
37
views
copy many files with big sizes over rsync
I have database server on AWS and the backup of databases are over 1000 files with sizes can reach 5GB,
I am using a script to copy the backup to my data center using rsync, but the copy is slow, I ...
0
votes
1
answer
29
views
Host with online server(Linux)
I purchased a server with ubuntu server.
Is it possible to create virtualhosts and connect them to a public domain to browse them?
Thank you,
Best regards,
user1053680
0
votes
1
answer
49
views
/var/mail/root - Shows in all bash output
I'm using Ubuntu 18.04.6 LTS and recently installed apt-get install mailutils. Have noticed that while running any command it is showing You have new mail in /var/mail/root additionally.
So i have ...
- 125
0
votes
2
answers
56
views
AWS CIDR Address is not within CIDR Address from VPC
In AWS have created VPC which CIDR is 10.0.0.24.I want to creates its two subnet.its public-subnet is in us-west-1a - IPv4 CIDR 10.0.0.0/24 thenwhen I create private subnet is in us-west-1b - ...
0
votes
0
answers
109
views
sudo su - has a 5 minute delay should I pop back to original use
We are working with ROcky linux 8.6 -
when we type sudo su - we are prompted for login and we get to root user no problem.
if we type exit we go back to the original user as is expected.
If we type ...
0
votes
3
answers
75
views
Postfix: How can I handle incoming mail for a single address, not the entire domain?
I've gotten my employer to configure the company-wide Exchange server to forward [email protected] to [email protected], a host I control. So far, so good. My Postfix configuration ...
- 131
1
vote
0
answers
118
views
How can I fix my unbearably slow NFS linux server?
I'm currently struggling with an extremely slow server providing home directories through NFS, and I cannot figure out the origin of the problem. It's all running on Nixos, but I don't think that's ...
- 11
0
votes
1
answer
46
views
How to do fuzzy match with linux alias
I usually use "root" to login in my linux, but I want to make shell forbid my dangerous command like fio --name=test --filename=/dev/nvme0n1, as /dev/nvme0n1 is my OS-drive.
So, how to ...
0
votes
1
answer
50
views
CentOS LVM Extension Trouble
We have a CentOS 8 server that has recently had a lvm fill up on available space. This was not our monitoring system since it watches the disk space and not the volume space. Regardless I am having ...
- 13
1
vote
1
answer
105
views
MariaDB randomly crashes
I've encountered a peculiar issue related to my MariaDB database instance (version 10.2) that causes my MariaDB service to stop unexpectedly. I've attempted to investigate the problem by regularly ...
- 19
0
votes
0
answers
39
views
How to get DHCP from other bands of DHCP server without DHCP relay package
This is the topology that I want to make of.
User gets DHCP from ex-ns, but can't use any packages on router such as isc-dhcp-relay, dnsmasq, dhcp-help, etc. I think it should use things like iptables ...
- 1
0
votes
0
answers
30
views
Is there a significant difference when virtualizing a VPN server?
Basically, my question is this: I have a "server"(a regular PC) with Debian installed. On this machine, I need to have a Tomcat service running at the same time as a VPN server service.
To ...
0
votes
0
answers
89
views
Need php-cgi process to show site URL too?
I have a CentOS 7 server. When I use "top" to view processes I can hit "c" to get the full command. I then see something like this:
17890 do1803 20 0 R 100.0 0.6 0:02.39 /...
- 101
1
vote
2
answers
128
views
How to make NFS server start if a disk mountpoint export fails to mount?
Consider the following /etc/exports:
/verbatim 192.168.0.0/255.255.255.0(rw,sync,no_subtree_check)
/sandisk 192.168.0.0/255.255.255.0(rw,sync,no_subtree_check)
/verbatim and /sandisk are mountpoints ...
- 33
2
votes
1
answer
48
views
Azure NFS migration from on prem NFS
Context: We are working on a data migration project involving the synchronization of data between an on-premises NFS filesystem and an Azure NFS-based file share. The goal is to ensure a seamless ...
- 21