Linux Admin L3

Day to day operational support and maintenance for Redhat 5,6 and 7 servers.Worked on Live upgrade from RHEL6 to RHEL7.Fixing vulnerabilities on Redhat linux.Patching linux OS and maintaining LCM.Working on SMTP, customized ftp service, vsftp.Worked in an environment of around 2000 servers.Creating LVM partitions, managing LVM partitions, extending LVM partitions.Troubleshooting of filesystem issues.Managing Users and Groups and applying security permission to users and directories.Managing permissions and ownerships.Configuring NTP on RHEL machines.Worked on scheduling scripts in con job.Supporting application team to have their pre-requisites installed/implemented in the servers.Passwordless ssh authentication using ssh-key generation.Setting environment variables for users as per their requirements.Monitoring logs and processes for linux servers.Worked on stopping iptables and disabling SELINUX.Installing or updating openjdk, oracle java and creating alternatives in linux servers.Creation of SOS report and proper vendor followup until we get the solution from them.Finding the root cause of issues by checking system logs to fix the issue.Installing & upgrading Vmware tool in linux VMs.Installation of client specific agents like Deep security, SIEM, ERD etc.Supporting infrastructure team for migration of servers from one DC to other.Managing ASM disks, we will perform creation and deletion of ASM disks in Database servers.Written scripts to monitor disk space, server load, CDS user group.Configured Network bonding, logrotate, samba security setting in all the linux servers.Worked on TSM backup restore on linux servers.Worked on nfs, autofs, cifs, ftp etc.Worked on business critical issues and resolved within SLA and provided proper RCA to customer.Preparing SOP for Linux activities.Worked on automation using shell script.Worked on onboarding project in which our team will prepare the design for new applications as perthe dc standards.Working as Linux operating system SME in the project, where we will prepare the design for the newapplication as per the security standards in the project.We will validate the servers whether it has beenbuild as per the standardsWorking in the datacenter migration team, where the servers will be migrated using vmconvertor forV2V and platespin tool for P2V or P2P.Helped team on preparing migration runbooks which helped during migrations. .