Deep dive into Kernel

$ dig www.google.com ; DiG 9.9.4-RedHat-9.9.4-51.el7_4.2 www.google.com;; global options: +cmd;; Got answer:;; ->>HEADER

http://sfixer.tistory.com/category/IMS http://www.nexpert.net/161

iwconfig eth1 essid MY_ESSID iwconfig eth1 key open 1234567890

LLDP : Link Layer Discovery Protocol- LLDP is discovery protocol between two direct interface.- for example, host A and L2 Switch Installation$ apt-get install lldp Test- following result shows that gaus02 discovered a neighbor called "gaus01-m.ngvt.com"- One of node's mac address become ChassisID- If it has other ports, it listed in a Portroot@gaus02-m:~# lldpcli show neighbors-----------------..

OVS 에서 VLAN 설정하는 방법 ovs-vsctl set Port br-int tag=50

Hostname 찾기 root@build-vm:/var/www/views# snmpwalk -c public -v 2c 192.168.1.8 .1.3.6.1.2.1.1.5.0iso.3.6.1.2.1.1.5.0 = STRING: "test-vm"

If your ssh client connects server slowly, edit /etc/ssh/sshd_config in ssh-server. #add UseDNS no

ㅇ VLAN 생성 - VLAN_100, VLAN_200 이란 vlan 그룹을 생성format: set vlans vlan-id root# set vlans VLAN_100 vlan-id 100root# set vlans VLAN_200 vlan-id 200 ㅇ Interface에 VLAN id taggingformat: set vlans interface root# set vlans VLAN_100 interface ge-0/0/0 ㅇ VLAN 설정 확인format: show vlansroot# show vlansVLAN_100 { vlan-id 100; interface { ge-0/0/0.0; ge-0/0/1.0; ge-0/0/2.0; ge-0/0/3.0; ge-0/0/4.0; ge-0/0/5.0; ..

nprobe -i -g -n -G -V 5 -G : 데몬 모드로 실행 -V : --flow-version : 5 (netflow v5) , 9(netflow v9), 10(ipfix) binary 패키지 http://www.nmon.net/packages/ubuntu/14.04/성능 분석Traffic Generator : pktgen-DPDK (10Gbps)root@cnode50-m:/tmp# nfdump -r /tmp/nfcapd.201411191056Date flow start Duration Proto Src IP Addr:Port Dst IP Addr:Port Packets Bytes Flows2014-11-19 10:55:15.896 111.248 TCP 192.168.0.1:1234 -> 19..

I finally installed 120Gbps (10Gbps * 6 lines * up&down) realtime traffic monitoring and analysis system. System Architecture: -16 computing nodes - 2.67GHz * 512 cores - 736 GB Memory - 64 TB Disk This system analyzes all traffic in KT's cloud data center. 전자신문 뉴스 : "대규모 트래픽 분석 시스템" http://www.etnews.com/201110050200