Ben's

* 참고링크: http://www.cyberciti.biz/tips/tag/ss-command The ss command is used to dump socket statistics. It allows showing information similar to netstat command. It can display more TCP and state information than other tools. It is a new, incredibly useful and faster (as compare to netstat) tool for tracking TCP connections and sockets. SS can provide information about: All TCP sockets. All UDP s..

* 각 yum 커널별 인식되는 CPU 갯수 EL: 1개(그 이상되더라도 1개로 인식) ELsmp: 1개~8개(그 이상되면 최대 8개까지 인식) ELlargesmp: 1개~n개(9개 이상도 인식함) * 설치방법 " yum install kernel-largesmp" [참고링크] http://zid-lux1.uibk.ac.at/linux/rpm2html/centos/4/os/x86_64/CentOS/RPMS/kernel-largesmp-2.6.9-89.EL.x86_64.html Summary: The Linux kernel compiled for machines with more than 64 CPUs on ppc64 and IA64 and with more than 8 CPUs on x86_64

이것은 대부분 조인시에 결과값을 새로운 테이블을 만들어서 거기서 select를 할때 생깁니다.

[nhko@nhkotest ~]$ dig @nhko.com txt chaos version.bind ; DiG 9.3.3rc2 @nhko.com txt chaos version.bind ; (1 server found) ;; global options: printcmd ;; Got answer: ;; ->>HEADER>HEADER

egrep -i 'error reading the headers' 아파치 error_log | awk '{print $8}' | sort -rn | uniq -c | sort -rn | wc -l

* 문제 내용: lspci 수동 업그레이드 시 lspci 명령을 내렸을때 아래와 같이 장치명이 Unknown device 로 표시되는 경우. 00:00.0 Class 0600: Unknown device 8086:2770 (rev 02) 00:02.0 Class 0300: Unknown device 8086:2772 (rev 02) 00:1c.0 Class 0604: Unknown device 8086:27d0 (rev 01) 00:1c.3 Class 0604: Unknown device 8086:27d6 (rev 01) 00:1d.0 Class 0c03: Unknown device 8086:27c8 (rev 01) 00:1d.1 Class 0c03: Unknown device 8086:27c9 (rev..

###################################################### /dev/sdb7 on /snapshot type ext3 (rw,data=writeback) [root@yum /]# time dd if=/dev/zero of=/snapshot/testfile bs=1024 count=2048000(write a 2Gfile) 2048000+0개의 레코드를 입력하였습니다 2048000+0개의 레코드를 출력하였습니다 real 0m52.466s user 0m0.288s sys 0m7.816s [root@yum snapshot]# time cat testfile (when test file was 20M file) real 0m14.482s user 0m0.004s sys 0..

* 일반 iptables 의 STRING match 모듈은 웹로그에 찍히는 패턴만 등록이 가능하기 때문에 방어가 제한적입니다. 그러나 아래와 같은 경우에서 hex-string 모듈을 이용하면 방어가 가능합니다. 61.98.219.208 - - [23/Jun/2009:11:55:26 +0900] "GET /images/700.exe HTTP/1.1" 403 300 "-" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0)" T 61.98.219.208:38333 -> xxx.xxx.xxx.xx:80 [AP] GET /images/700.exe HTTP/1.1..Accept: */*..Cache-Control: no-cache..Ryeol-Magic: My Magic..