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.

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Systemd: Supervising process XXXX which is not our child. We'll most likely not notice when it exits

I've created a custom service file which looks like this: cat /etc/systemd/system/aaa.service [Unit] Description=aaa main application After=syslog.target network-online.target [Service] Type=...
6
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1answer
836 views

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=="...
6
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1answer
663 views

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 ...
5
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1answer
2k views

CentOS 7: Fresh Install Firewalld doesn't work at all (Fatal Error: No IPv4 and IPv6 firewall)

I have the following problem. I just did an dvd CenOS 7 installation. After I boot into the system I normally login as the root user. From there I'm trying to configure Firewall on my server. As I'm ...
5
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0answers
2k views

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. ...
4
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1answer
106 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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0answers
766 views

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 ...
4
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0answers
116 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 ...
4
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0answers
408 views

How can I track down why the rpm DB on my servers keeps getting corrupted?

Running Centos 7 (various versions) The rpm DB on my servers keeps getting corrupted. It seems like every few weeks I have to do an rpm rebuild on a server or two. Where should I look to see what ...
4
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1answer
3k 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
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2answers
4k 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, ...
4
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1answer
2k views

How do i get Strongswan / IPTables to route data back to my road warrior client correctly?

I have a simple VPN. I have a client on 10.185.28.241 who gets a virtual IP of 10.42.42.0/24 from the VPN which is located at 10.112.18.105 and is providing access to machines in the 10.112.0.0/16 ...
4
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1answer
347 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 ...
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559 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
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1answer
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
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0answers
706 views

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 ...
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416 views

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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0answers
256 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 ...
3
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0answers
275 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
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1answer
2k views

Is it possible to install Samba 3 on CentOS 7?

Trying to address a compatibility problem with Samba 4, that comes with CentOS 7, I consider downgrading to Samba 3. However, based on this page https://pkgs.org/download/samba, and elsewhere I ...
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0answers
257 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 ...
3
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0answers
265 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 ...
3
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0answers
340 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. ...
3
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1answer
29k views

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 ...
3
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0answers
3k views

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 /...
3
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0answers
111 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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0answers
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 ...
3
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1answer
5k 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 - ...
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0answers
3k views

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
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1answer
382 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 ...
3
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1answer
5k views

Failed at step EXEC spawning /usr/libexec/mariadb-prepare-db-dir

a bit of a newbie here so mind my obliviousness. I'm trying to install mariadb on a fresh Centos 7 server, though upon running "systemctl start mariadb.service" I get this malarkey: Job for ...
3
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1answer
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-...
3
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2answers
1k views

NetworkManager - do not allow user to disable network or connection

By default, users that are logged in on the system are able to completely disable network or connection, is there a way to disable this? Thanks
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0answers
21 views

df differs from du a lot, nfsd service seems matter

I know there have been a lot of discussion on the df/du discrepancy topic. But here I’d post a special issue and ask for some hints. here is the detail( with a hardware raid5 with 6 sas disks) system ...
2
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4answers
141 views

mysqld crashing almost every hour - mysqld invoked oom-killer

I am running wordpress on a centOS digital ocean droplet my mysql keeps crashing almost every hour -- with an out of memory error manually restarting mysqld brings it back up via sudo service mysqld ...
2
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1answer
71 views

CentOS command not found

When I login to my CentOS 7 Server I get a couple of errors. Similar command is: 'tty' bash: ls: command not found... Similar command is: 'lz' /usr/libexec/grepconf.sh: line 5: grep: command not found ...
2
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0answers
82 views

Centos 7: Cannot curl localhost nor internal IP : no route to host

Centos 7, lamp stack. ​ firewall is turned off, sealinux is disabled, Iptables looks fine ​ if you to localhost/api.php or internal-ip/api.php from a browser, it works fine, if you ping it's fine, if ...
2
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1answer
145 views

Check XFS project quota on NFS client

I am implementing project quotas on a file server (Centos 7.8.2003) that has data volumne formatted using XFS. File access to this server will occur using NFS. I know how to check user quotas on the ...
2
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1answer
109 views

firewalld, `--add-rich-rule` and missing blacklist set

My server uses Centos8 quite recently installed (~1 year). After trying to ban an IP: firewall-cmd --permanent --zone=extz --add-rich-rule='rule family="ipv4" source address="49.88.112....
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0answers
1k 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 ...
2
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0answers
232 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. ...
2
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0answers
47 views

Can I delete `mysql` os user which is created during mysql installation?

I have installed MySQL Community Server 5.7.28 on a CentOS 7. I have observed that there is an OS level user mysql created during installation. As per our security team, we can have only one ...
2
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0answers
45 views

I'm getting error during HA configuration for KVM on CentOS

After adding all nodes and resource agents in my cluster I'm getting this error please someone suggest me something. Please take a look in the image-
2
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1answer
589 views

GlusterFS not running on correct port! (peer disconnected / brick not starting)

On CentOS 7 witch two bricks on srv1 and srv2 I've upgraded gluster from 313 to 6 by using yum. I then rebooted server 1, started and mounted the drive successfully. This is my mount command: /usr/...
2
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1answer
4k views

CentOS 7: Failed to restart mysql.service: Unit not found

I had installed and started Percona XtraDB Cluster 5.7 on 3 nodes. Everything went fine, until I had rebooted my first node. From then mysql.service couldn't be (re)started normally: [root@percona1]# ...
2
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0answers
494 views

Failed downloading file. Nginx aio read /path/to/file failed (22: Invalid argument)

On our site we added the ability to download our video files. We use nginx on our servers. The weird issue is now that sometimes files are downloadable and sometimes not. The error we receive in the ...
2
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1answer
111 views

Can I use variables when referring to volume groups and logical volumes in a kickstart file?

I have variables set up in the %pre section that look like this: %pre VOLGROUP=$(lvdisplay |grep VG | awk '{print $3}' |head -1) vgchange -a y $VOLGROUP ROOTVOL=$(lvdisplay |grep root | grep Path | ...
2
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1answer
708 views

Kickstart install: what disk name should I tell Anaconda to use? (Installer running from USB thumb drive.)

I'm running the CentOS 7.6 installer from a USB thumb drive using a kickstart file. I'm installing to a system that has only one disk. In the bash shell of the installer, my system's hard drive shows ...
2
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1answer
996 views

SSSD+Samba+SSH GSSAPI authentication issues

I am configuring SSSD+Samba+SSH on CentOS 7.6. So far I have managed to get all 3 at least working. SSSD is configured and joined using realm join. Samba is configured and connected to AD via net ads ...
2
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0answers
2k views

SSH Tunnel - channel 3: open failed: administratively prohibited: open failed

ssh -D 9090 user@host when I try to request web pages through socks5 (127.0.0.1:9090) I get: channel 3: open failed: administratively prohibited: open failed server sshd_config: #MaxStartups 10:30:...

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