Questions tagged [centos7]
CentOS is a Linux distribution standing for "Community ENTerprise Operating System" and is a rebuild of "Red Hat Enterprise Linux" (RHEL), belonging to the same company that distributes RHEL (Red Hat, Inc.). The "CentOS7" tag refers to versions 7.x-xxxx of CentOS, working only on 64-bit hardware. Maintenance updates for CentOS/RHEL 7 will stop on June 30, 2024, with full updates ceasing in winter of 2019.
1,063
questions with no upvoted or accepted answers
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answer
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Determine name of Hyper-V host of Linux guest VM
I would like to be able to determine which Hyper-V host a particular CentOS 7 VM is running on. In a Windows VM this is stored in HKLM:\SOFTWARE\Microsoft\Virtual Machine\Guest\Parameters. Is anyone ...
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6
votes
0
answers
3k
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Ensure systemd wait for IPv6 before start service unit
When I have a service listening on a specific IPv6 address, it fails on boot, claiming that the address is still not available. This happens to every service that is listening on specific addresses.
...
6
votes
1
answer
2k
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udev rule not applied on boot for mounted disk
I'm trying to persist a readahead rule on a mounted drive to use with mongodb.
The mount is persisted using /etc/fstab and that works as expected.
I have added a udev rule ACTION=="add", KERNEL=="...
- 161
5
votes
2
answers
10k
views
Kubeadm 1.24 with containerd. Kubeadm init fail (centos 7)
I try to install a single node cluster on centos 7, with kubadm 1.24 and with containerd,
i followed the installation steps,
and i did:
containerd config default > /etc/containerd/config.toml
and ...
- 81
5
votes
2
answers
6k
views
Linux SMB to \\domainname ends up "tree connect failed: NT_STATUS_DUPLICATE_NAME "
Issue:
From CentOS7 machine:
smbclient -L %domainname%.com --user=%username%
Result:
tree connect failed: NT_STATUS_DUPLICATE_NAME
This is especially when I try to connect to //domainname.com, ...
- 189
5
votes
0
answers
1k
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What SELinux type should I apply on my Unix socket?
I have a Gunicorn socket file: /opt/rtd/gunicorn/run.sock. I need nginx to be able to open this socket and write to it.
When I run sesearch --allow -s httpd_t | grep unix_stream_socket I noticed that ...
5
votes
1
answer
36k
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CentOS 7 Unable to Resolve Any Host Names
New to Linux and looking for friendly assistance.
My company is re-configuring our network DNS infrastructure to point our internal DNS servers at two new CentOS 7 / BIND 9 machines in our DMZ ...
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4
votes
1
answer
191
views
Python 3.6.3 virtual environment issue in CentOS7 - "Error: Could not connect to Docker (is it running?)"
I have a virtualenv issue in my CentOS7 VM:
Checking for virtualenv...
Activating virtual environment /home/crimson/venv/python3
/home/crimson/venv/python3/myvra.json matches /home/crimson/venv/myvra....
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4
votes
0
answers
1k
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Are there any known common causes of "Cannot kill process: Success!" in error.log?
Operating system: CentOS Linux release 7.6.1810 (Core)
Error log: /var/log/httpd/error.log
Apache version: Apache/2.4.6
In attempting to debug a PHP cron task, I am seeing some segfaults in error....
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4
votes
0
answers
2k
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How does the Linux NFS server implementation of setclientid work?
Does anyone understand the NFS protocol (Version 4) or the Linux NFS server implementation of it well enough to explain how setclientid negotiates authentication?
Background:
I have a CentOS 7 ...
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4
votes
0
answers
811
views
`systemctl show` outputs incorrect MemoryCurrent value
on one box, systemctl show get an incorrect value for unit memory usage:
$ systemctl show crond | grep MemoryCurrent
MemoryCurrent=18446744073709551615
18446744073709551615 == UINT64_MAX, this must ...
- 143
4
votes
0
answers
210
views
Network access stalls for some time on centos7 + zfs + samba installation
I have storage server with CentOS7 with 4 HDDs running on raidz (Raid 5). I access the files on it via samba.
When I copy files from it or watch movies sometimes the reading from samba is blocked for ...
- 288
4
votes
1
answer
7k
views
Scripts in /etc/profile.d are being executed twice on login
Background Info:
I am trying to configure a Linux server running CentOS 7 for multiple users. After installing java I want to globally set the $JAVA_HOME environment variable for all users and add it ...
- 141
4
votes
1
answer
5k
views
Apache 2.4 with Kerberos Auth and LDAP Authorization
I am trying to setup an Apache SVN repository with Kerberos authentication and LDAP group membership authorization, so that only users that belong to a specific group can access it. Kerberos auth on ...
4
votes
0
answers
2k
views
Apache sometimes not starting after reboot
Sometimes, after my server (Cent OS7, default repository) reboots, Apache is not started automatically. To fix this, I reboot the server one more time, and then it works.
My Apache error logs shows ...
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4
votes
1
answer
591
views
Can't firewalld replace iptables?
I used Iptables on Centos 6.5 and tried to translate iptables rules into firewalld rules on centos 7.
However, with firewalld, i have discovered i am unable to
drop packets in invalid states
create ...
- 631
4
votes
1
answer
8k
views
Send mail service start error
I installed sendmail on CentOS based on some tutorial. When I start sendmail, it showing sendmail failed error.
Here the following command result:
systemctl status sendmail
sendmail.service - ...
- 61
4
votes
0
answers
719
views
pppd terminated bya SIGTERM in Centos 7 -- who's sending it?
Folks,
I created a script to keep a persistent "emergency" connection with a 3G modem, so I can access my CentOS 7 makeshift server remotely if the usual network fails. Everything works for a few ...
4
votes
1
answer
2k
views
CentOS7 systemctl calling ExecStop on reboot after my procceses are already killed
I have a systemd script which is as follows:
[Unit]
Description=My sites
Before=shutdown.target reboot.target halt.target
[Service]
Type=oneshot
ExecStart=/bin/bash -c '/etc/xxx/mySites start'
...
3
votes
0
answers
593
views
Add a server to an already running DRBD9 configuration
I am on CentOS7 and I have an existing two-cluster HA node running pacemaker (1.1.23-1.el7_9.1) and DRBD (kmod-drbd90-9.0.22-3.el7_9). The backing partition for the DRBD drive is LUKS encrypted. We ...
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3
votes
1
answer
1k
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Trying to use keepalived for failover and forwarding but getting "Keepalived_healthcheckers[1706]: TCP socket bind failed. Rescheduling."
The goal is to get two different CentOS 7 VMs with keepalived installed to perform failover with VIP 192.168.1.11 and also forward the http (to become https shortly after this works) traffic to a ...
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3
votes
1
answer
9k
views
id: user: no such user
I'm using Centos 7 to authenticate locally Active directory users using kerberos. I joined the realm with the Administrator and i can login/ssh through it/with it, nslookup working fine, and adcli ...
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3
votes
0
answers
4k
views
CentOS: how to fix GDBus.Error:org.freedesktop.DBus.Error.LimitsExceeded (Maximum active connections)?
On a CentOS 7 server I'm getting this error while trying to reboot:
# reboot
Error getting authority: Error initializing authority: GDBus.Error:org.freedesktop.DBus.Error.LimitsExceeded: The ...
- 131
3
votes
0
answers
6k
views
Booting a squashed filesystem from ISO
I am trying to create a UEFI bootable CD ISO with a squashed filesystem from a virtual machine, which I provisioned with the stuff I need.
To explain:
I use packer and a kickstart file to install ...
- 131
3
votes
0
answers
2k
views
Memcached fails/crashes every few hours
I have a CentOS 7 server with Memcached. There are a lot of requests, and usually after a few hours, the memcached daemon crashes. I always restart the service, but it crashes again a few hours later.
...
- 238
3
votes
0
answers
2k
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Obscure systemd-logind message on Centos 7 running on OpenVZ 7
I am seeing the message below appear several times at random times on a Centos 7 64-bit virtual private server running on OpenVZ 7. I have no idea what it means, how to fix it or if it can be safely ...
- 35
3
votes
0
answers
773
views
Rsyslog messages not making it to local logfile
I've been tasked with setting up longer/better log retention for our postgres servers, but after configuring postgres to ship logs to syslog via local0 I've found that they never actually hit the ...
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3
votes
0
answers
7k
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Exhausted all hosts available for retrying build failures for instance
Trying to make a proof of concept cloud by following this guide https://www.rdoproject.org/install/packstack/
I managed to get OpenStack installed and I'm able to access the dashboard. When I go to ...
- 157
3
votes
0
answers
6k
views
How to find out what is blocking a port in Centos 7?
I'm trying to make a mailserver with postfix/dovecot but I'm stuck. The problem is I cannot connect to some of the ports I want open, for example 587. As far as I can tell the port is open and ...
- 853
3
votes
0
answers
619
views
How to create a Linux virtual machine in AWS with multiple network interface cards each having a public IP
AWS. Centos 7.5 m5.large EC2 instance. VPC with 2 subnets. The instance has two network interfaces, one per a subnet. A Network Security Group is configured to allow all TCP inbound and outbound ...
- 3,918
3
votes
0
answers
311
views
Enable cgroups on Beowulf compute nodes
We are running a Beowulf cluster using the Scyld distribution from Penguin Computing, and it looks like cgroups are configured on the head node, but not the compute nodes. I'm trying to configure ...
- 1,504
3
votes
0
answers
577
views
FreeIPA : Keytab File for Adding Multiple NFS Clients
I'm relatively new to IPA and have been practicing setting up Kerberized NFS. I succeeded in initially sharing a directory from my VM Server1 to Server2.
I accomplished the above by adding the NFS ...
3
votes
1
answer
2k
views
Galera cluster - cannot start MariaDB (CentOS7)
I'm trying to install a Galera cluster with 3 mariadb VM's (all of them CentOS 7). I've never done this before, so I was following this guide:
http://tunnelix.com/mariadb-galera-cluster-installation/
...
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3
votes
1
answer
3k
views
EDAC memory error after upgrade server SuperMicro with CentOS 7. Is these specific errors of motherboard, OS or broken RAM module?
I have server on SuperMicro MBD-X9DRD-EF motherboard. It worked well at CentOS7 during the year with one CPU (Intel Original Xeon X6 E5-2620v2) and 128 Gb (8x16 Gb) LVDDR (1600MHz Crucial ECC Reg RTL (...
3
votes
1
answer
3k
views
Apache Default Virtual Host not loaded in right order
Apache/2.4.6 (CentOS)
For a while now, I've had a catchall page setup for my Apache server so bots would not crawl my main site unless they had my domain name.
Recently however, I noticed this no ...
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3
votes
0
answers
479
views
Can cgclassify be used with systemd based resource management?
So as of redhat/centos 7, system resource management got a big overhaul. Before redhat/centos 7, cgroups were run using libcgroup packages and daemons like cgred.
Before, if I wanted to move a ...
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3
votes
0
answers
493
views
How to trigger initial login so user slice gets created
I may be taking the wrong approach here, but the new centos 7 implementation of cgroups lets you put limits on user's access to system resources by attaching said limits to their slices.
Ie.
...
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3
votes
1
answer
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mount(2): Stale file handle NFS after update server to Debian 8
I've several server that mounting NFS on remote backups server
Everything worked until I did an update on the NFS server to Debian Jessie.
Now some machines work and others not work.
Try several ...
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3
votes
0
answers
3k
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Why is CentOS 7 ignoring NETMASK?
I have a networking issue that I eventually tracked down to an incorrect network prefix setting.
ip addr is reporting that the current prefix is /8 when it should be /24.
However, when I look in /...
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3
votes
0
answers
202
views
Postfix STARTTLS works in LAN but not externally
if I connect in LAN on port 25 to my mail server, it offers STARTTLS
telnet mailserver.com 25
Trying 192.168.0.x...
Connected to mailserver.com
Escape character is '^]'.
220 mailserver.com ESMTP ...
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3
votes
0
answers
3k
views
HAProxy failing at random times (backend has no server available!)
I have a CentOS 7.1 (x64) droplet configured to load balance between 2 apache/php servers.
I have it working perfectly, but randomly throughout the day it reports the following:
haproxy[12947]: ...
- 81
3
votes
0
answers
3k
views
Are the i40e and ixgbe drivers really used by our Intel NICs?
We recently got two QCT 2U4Node high-density servers. Each node is equipped with a XL710 dual 40G NIC with two QSPF+ ports and two QCT mezz cards that sport Intel 82599 and dual 10G SPF+ ports for a ...
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3
votes
0
answers
4k
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Can't read ACL on NFS4 share, Solaris 10 client, CentOS 7 server
First off, please excuse me if my question isn't well formed, this is my first post on serverfault :)
I have successfully deployed LDAP and Kerberos authentication in a mixed Linux/Windows/Solaris ...
3
votes
1
answer
2k
views
Create KVM storage pool using a ext4 formatted drive
I have a secondary hdd that I would like to use as a storage pool for my KVM host.
Here is the xml file I use to create the storage pool,
<pool type='disk'>
<name>guest_images_disk<...
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3
votes
1
answer
727
views
How to redirect FORWARD proxy users to webpage using mod_proxy - apache
I have searched quite a lot for a solution and most answers pertain to either proxypass (reverse proxy) or are not relevant.
End users' web browsers are configured to use the Apache proxy server.
I ...
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3
votes
1
answer
2k
views
Fail2ban on centos 7 does not add rule to firewall. Firewall-cmd used on system
I installed the latest fail2ban from centos/epel I have added the ssh enabled option in jail.local. I have tried with action and banaction = firewallcmd-ipset neither made any difference. iptables-...
- 303
2
votes
0
answers
469
views
cachefilesd - how to ensure file is copied from local cache?
I have setup cachefilesd and to check if it is correct I verified following:
cachefilesd service is running
NFS storage is mounted with -o fsc and able to see FSC set to yes in /proc/fs/nfsfs/volumes
...
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2
votes
1
answer
879
views
what is best config for php-fpm and nginx with this server?
I have a server with following specs and was wondering what's the best config I can set for nginx and php-fpm?
RAM: 96GB
CPU: 48 Cores
SSD: 200GB
OS: Drupal
Daily users: 52k to 55K
PHP: 7.3
Mysql: 8.0
...
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2
votes
1
answer
222
views
CentOS 7 startup error - unregistered net_device
I see these errors upon startup of my CentOS 7 server. It has a Solarflare SFN8542 adapter. How can I fix this? I am pretty new to Linux.
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2
votes
0
answers
828
views
Linux host routing VLAN traffic cannot receive or make network connections
I have a CentOS 7 system that has three interfaces. I recently
converted one on those interfaces to using VLANs. This system servers
as a firewall and router between the various networks. ...
- 21