CT's Tech Notes

This note provides steps for up and running haproxy loadbalancer for http service. Install haproxy rpm yum install haproxy Edit haproxy.cfg vi /etc/haproxy/haproxy.cfg global maxconn 100000 user haproxy group haproxy defaults #log global mode http # option httplog # option dontlognull retries 3 option redispatch maxconn 100000 contimeout 5000 clitimeout 50000 srvtimeout 50000 VIP address. Do not add config at /etc/sysctl.conf listen webfarm 192.168.1.3:80 It can be tcp or http mode http # stats enable # stats auth someuser:somepassword balance roundrobin # allow to track source ip option forwardfor option httpchk HEAD /linkcheck.html HTTP/1.0 server webA 192.168.1.1:80 cookie A check server webB 192.168.1.2:80 cookie B check Edit system parameter vi /etc/sysctl.conf net.ipv4.ip_nonlocal_bind = 1

This steps will be general procedures to edit initial ram disk Create temporary directory. For this case, i will create /boot/img mkdir /boot/img Change initrd file name mv /boot/initrd.xx.img /boot/img/initrd.xx.img.gz Unzip and extract image cd /boot/img gunzip initrd.xx.img.gz cpio -idumv < initrd.xx.img.gz You will have extracted directory. Now you can edit or add necessary drivers. This will be how to repackage Go to your extracted temporary directory. For my case, /boot/img find . | cpio -o -H newc | gzip -11 > ../initrd.xx.img

cpio is a useful tool to archive Linux system. In this article, we are going to archive / partition which is mounted from sda11 partition. ###Archive ssh root@192.168.1.104 "find / -xdev -print0 | cpio --null --create" > sda11.cpio ###Extract cpio --extract --no-absolute-filenames --file=sda11.cpio For the /dev directory, recommended to be archived by tar command ssh root@192.168.1.104 "tar -c /dev" > dev.tar

Edit /etc/inittab co1:2345:respawn:/sbin/agetty ttyS0 9600 vt100 co2:2345:respawn:/sbin/agetty ttyS1 9600 vt100 Restart init init q