The server crashes due to an invalid pointer when executing an I/O generating from the aio code. A discrepancy with how the kernel updates the tail pointer with memory-mapped aio queues can corrupt the tracking of aio I/O operations. This causes aio queues killed prematurely while I/O operations are still active. To resolve this error, …

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Add following settings in /etc/multipath.conf defaults { polling_interval 5 no_path_retry 4 find_multipaths yes checker_timeout 5 max_fds 8192 fast_io_fail_tmo 4 dev_loss_tmo 19 user_friendly_names yes } Reload multipath service with service multipathd reload

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This article will discuss, where the Ansible configuration files are located and how Ansible selects them and how we can edit default settings. Configuring Ansible: The Ansible behavior can be customized by modifying settings in the Ansible configuration files. Ansible chooses its configuration file from one of many locations on the control node.  /etc/ansible/ansible.cfg This …

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Multiple bonding modes in a Linux operating system are given below: balance-alb (fault tolerance and load balancing) balance-tlb (fault tolerance and load balancing) active-backup (fault tolerance) broadcast (fault tolerance) balance-rr (fault tolerance and load balancing) 802.3ad (fault tolerance and load balancing) balance-xor (fault tolerance and load balancing) We will use Network Manager CLI to add …

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Mount NFS share on NFS clients without cache. First, unmount NFS share and then remount NFS share with noac and lookupcache=none

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The kickstart automatic installation of the Linux operating system fails but the normal install is successful. To resolve this issue follow the steps given below: Add clearpart --all --drives=${devname} --initlabel in kickstart disk section. This will delete partition table of disk. If the above option does not resolve the issue add zerombr option above clearpart …

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Add -w /NFS-MOUNT/ -p wa -k NFS-MOUNT line at the end of file /etc/audit/audit.rules [root@COMPUTE ~]# cat /etc/audit/audit.rules ## This file is automatically generated from /etc/audit/rules.d -D -b 8192 -f 1 -w /NFS-MOUNT/ -p wa -k NFS-MOUNT Execute the following command to restart auditd service service auditd restart

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This error is resolved by upgrading the directory server base package in your Linux operating system. The issue arises because of an unindexed search. Check directory server logs for details.

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In spite of /usr/lib/cups/daemon/cups-lpd denial to read access sock_file cups.sock, cups-lpd will successfully migrate print jobs received via LPD to the local CUPS server. You can either ignore this issue or create a custom SELinux policy module. The steps to create a custom SELinux policy module are listed below: yum -y install setools-console yum-utils policycoreutils-devel …

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If attackers request using your CGI script open an outgoing network connection than this can be redirected to attackers controlled proxy. This can lead to denial of service and potentially occurs while using httpd mod_cgi This issue can be resolved via mod_header in httpd configuration. RequestHeader unset Proxy early

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IPv6 requires ICMPv6 neighbour solicitation and neighbour advertisement packets to create IPv6 connectivity. These packets are used to resolve IPv6 addresses to link-layer (ethernet). Add new icmptypes for neighbour solicitation and neighbour advertisement firewall-cmd --permanent --new-icmptype=neighbour-solicitation firewall-cmd --permanent --new-icmptype=neighbour-advertisement Remove destination IPv4 firewall-cmd --permanent --icmptype=neighbour-solicitation --remove-destination=ipv4 firewall-cmd --permanent --icmptype=neighbour-advertisement --remove-destination=ipv4 Attach icmptypes to the –zone=drop …

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[500 OOPS: child died] is a permanent negative error reply, whereas [421 Timeout] is a temporary negative error reply. Downgrade vsftpd to a lower version to resolve this issue. Check vsftpd man pages for details on Transient Negative Completion reply and Permanent Negative Completion reply.

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Turn off the instance, and then using the nova image-create command, create a snapshot of the nova instance. openstack server list openstack server image create server2 --name server2-snapshot After the snapshot is created, it will be visible at a glance. Confirm snapshot in a glance with; openstack image list Download snapshot image openstack image save …

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To clean up old ceilometer data in OpenStack, perform the following steps: First of all, stop the Telemetry service. systemctl stop openstack-ceilometer-collector openstack-ceilometer-notification openstack-gnocchi-metricd openstack-gnocchi-statsd openstack-aodh-evaluator openstack-aodh-listener openstack-aodh-notifier openstack-ceilometer-central Stop MongoDB service by entering the following on shell prompt. systemctl stop mongod Delete all files in /var/lib/mongodb and then restart MongoDB. cd /var/lib/mongodb rm -r …

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