8. Redhat Linux : RHCE 6
Log files:
* variable messages are stored in /var file * three types of logs: system logs ( /var/log/messages ) secure logs ( /var/log/secure ) kernel logs ( /var/log/dmesg ) * rsyslogd generates the logs in RHEL 6 * syslogd + klogd in RHEL 5 * 546 is the port for logs * config file is /etc/rsyslog.conf 2 fields: selector action * NTP (Network time protocol) is used to maintain network time * logrotate is used to reuse the same server in particular period after backup * /etc/logrotate.conf * /etc/hosts is called cache DNS * Primary DNS: * Secondary DNS: to support primary, so it is called failover. also be used in load balancing * Teritiary DNS: can be used as cache * Domain server gives the local mounting(eg: gmail) * LDAP : Light weight access protocol * NIS(Network Information Storage) : Active directory for linux ISCSI
* scsi-target-utils is the package * tgtd is the service * /etc/tgt/target.conf Steps to do at server: 1. fdisk /dev/sda 2. partprobe /dev/sda 3. pvcreate /dev/sdxy 4. vgcreate vg1 /dev/sdxy 5. lvcreate -n lv1 -L 460M vg1 6. yum install scsi-target -y 7. vim /etc/tgt/targets.conf 8. service tgtd restart 9. chkconfig iptables on Steps to do at client: 1. yum install scsi-target -y 2. iscsiadm -m discovery -t st -p server_ip 3. iscsiadm -m node -T iqn.2015-04.com.exapmle:server1.target1 -l 4. fdisk -l 5. iscsiadm -m node -T iqn.2015-16.com.example:server.target1 -u 6. mount TCP Wrappers
* /etc/hosts.allow stores the users to deny VSFTPD:server1.exapmle.com * /etc/hosts.deny Disk Quota
* to give some space reserved for users * 2 limits: soft limits(if it cross the limit, say 1 GB, it will display warning and allow to create more files) hard limits(if it cross the limit, say 1 GB, it will not display warning and do not allow to create more files) * edquota to edit quota * repquota for listing quotas
/* Commands for the day: -------------------- * edquota username
*/
