CTRL+Vet descendre jusqu'à la ligne que l'on veut commenter.
s/^/#/
s/^#//
wget --no-check-certificate --no-cookies --header "Cookie: oraclelicense=accept-securebackup-cookie" http://download.oracle.com/otn-pub/java/jdk/8u65-b17/jdk-8u65-linux-x64.rpmTAR.GZ
wget --no-check-certificate --no-cookies --header "Cookie: oraclelicense=accept-securebackup-cookie" http://download.oracle.com/otn-pub/java/jdk/8u65-b17/jdk-8u65-linux-x64.tar.gzRPM (en utilisant CURL)
curl -v -j -k -L -H "Cookie: oraclelicense=accept-securebackup-cookie" http://download.oracle.com/otn-pub/java/jdk/8u65-b17/jdk-8u65-linux-x64.rpm > jdk-8u65-linux-x64.rpm
git reset --hard HEAD~1
HEAD is now at 444b1cf Rhoo
git push
To /tmp/repo
! [rejected] master -> master (non-fast-forward)
error: failed to push some refs to '/tmp/repo'
git push -f
Total 0 (delta 0), reused 0 (delta 0)
To /tmp/repo
+ b67c343...444b1cf master -> master (forced update)
git diff HEAD^ | patch --reverse
git revert HEAD~3..HEAD
git revert 444b1cff
The Tor network is a group of volunteer-operated servers that allows people to improve their privacy and security on the Internet. Tor's users employ this network by connecting through a series of virtual tunnels rather than making a direct connection, thus allowing both organizations and individuals to share information over public networks without compromising their privacy. Along the same line, Tor is an effective censorship circumvention tool, allowing its users to reach otherwise blocked destinations or content. Tor can also be used as a building block for software developers to create new communication tools with built-in privacy features.Individuals use Tor to keep websites from tracking them and their family members, or to connect to news sites, instant messaging services, or the like when these are blocked by their local Internet providers. Tor's hidden services let users publish web sites and other services without needing to reveal the location of the site. Individuals also use Tor for socially sensitive communication: chat rooms and web forums for rape and abuse survivors, or people with illnesses.Journalists use Tor to communicate more safely with whistleblowers and dissidents. Non-governmental organizations (NGOs) use Tor to allow their workers to connect to their home website while they're in a foreign country, without notifying everybody nearby that they're working with that organization.Groups such as Indymedia recommend Tor for safeguarding their members' online privacy and security. Activist groups like the Electronic Frontier Foundation (EFF) recommend Tor as a mechanism for maintaining civil liberties online. Corporations use Tor as a safe way to conduct competitive analysis, and to protect sensitive procurement patterns from eavesdroppers. They also use it to replace traditional VPNs, which reveal the exact amount and timing of communication. Which locations have employees working late? Which locations have employees consulting job-hunting websites? Which research divisions are communicating with the company's patent lawyers?A branch of the U.S. Navy uses Tor for open source intelligence gathering, and one of its teams used Tor while deployed in the Middle East recently. Law enforcement uses Tor for visiting or surveilling web sites without leaving government IP addresses in their web logs, and for security during sting operations.The variety of people who use Tor is actually part of what makes it so secure. Tor hides you among the other users on the network, so the more populous and diverse the user base for Tor is, the more your anonymity will be protected.
Using Tor protects you against a common form of Internet surveillance known as "traffic analysis." Traffic analysis can be used to infer who is talking to whom over a public network. Knowing the source and destination of your Internet traffic allows others to track your behavior and interests. This can impact your checkbook if, for example, an e-commerce site uses price discrimination based on your country or institution of origin. It can even threaten your job and physical safety by revealing who and where you are. For example, if you're travelling abroad and you connect to your employer's computers to check or send mail, you can inadvertently reveal your national origin and professional affiliation to anyone observing the network, even if the connection is encrypted.How does traffic analysis work? Internet data packets have two parts: a data payload and a header used for routing. The data payload is whatever is being sent, whether that's an email message, a web page, or an audio file. Even if you encrypt the data payload of your communications, traffic analysis still reveals a great deal about what you're doing and, possibly, what you're saying. That's because it focuses on the header, which discloses source, destination, size, timing, and so on.A basic problem for the privacy minded is that the recipient of your communications can see that you sent it by looking at headers. So can authorized intermediaries like Internet service providers, and sometimes unauthorized intermediaries as well. A very simple form of traffic analysis might involve sitting somewhere between sender and recipient on the network, looking at headers.But there are also more powerful kinds of traffic analysis. Some attackers spy on multiple parts of the Internet and use sophisticated statistical techniques to track the communications patterns of many different organizations and individuals. Encryption does not help against these attackers, since it only hides the content of Internet traffic, not the headers.
Tor helps to reduce the risks of both simple and sophisticated traffic analysis by distributing your transactions over several places on the Internet, so no single point can link you to your destination. The idea is similar to using a twisty, hard-to-follow route in order to throw off somebody who is tailing you — and then periodically erasing your footprints. Instead of taking a direct route from source to destination, data packets on the Tor network take a random pathway through several relays that cover your tracks so no observer at any single point can tell where the data came from or where it's going.To create a private network pathway with Tor, the user's software or client incrementally builds a circuit of encrypted connections through relays on the network. The circuit is extended one hop at a time, and each relay along the way knows only which relay gave it data and which relay it is giving data to. No individual relay ever knows the complete path that a data packet has taken. The client negotiates a separate set of encryption keys for each hop along the circuit to ensure that each hop can't trace these connections as they pass through.
Once a circuit has been established, many kinds of data can be exchanged and several different sorts of software applications can be deployed over the Tor network. Because each relay sees no more than one hop in the circuit, neither an eavesdropper nor a compromised relay can use traffic analysis to link the connection's source and destination. Tor only works for TCP streams and can be used by any application with SOCKS support.For efficiency, the Tor software uses the same circuit for connections that happen within the same ten minutes or so. Later requests are given a new circuit, to keep people from linking your earlier actions to the new ones.
Tor can't solve all anonymity problems. It focuses only on protecting the transport of data. You need to use protocol-specific support software if you don't want the sites you visit to see your identifying information. For example, you can use Tor Browser while browsing the web to withhold some information about your computer's configuration.Also, to protect your anonymity, be smart. Don't provide your name or other revealing information in web forms. Be aware that, like all anonymizing networks that are fast enough for web browsing, Tor does not provide protection against end-to-end timing attacks: If your attacker can watch the traffic coming out of your computer, and also the traffic arriving at your chosen destination, he can use statistical analysis to discover that they are part of the same circuit.
SOURCE : https://www.torproject.org/about/overview.html.enProviding a usable anonymizing network on the Internet today is an ongoing challenge. We want software that meets users' needs. We also want to keep the network up and running in a way that handles as many users as possible. Security and usability don't have to be at odds: As Tor's usability increases, it will attract more users, which will increase the possible sources and destinations of each communication, thus increasing security for everyone. We're making progress, but we need your help. Please consider running a relay or volunteering as a developer.Ongoing trends in law, policy, and technology threaten anonymity as never before, undermining our ability to speak and read freely online. These trends also undermine national security and critical infrastructure by making communication among individuals, organizations, corporations, and governments more vulnerable to analysis. Each new user and relay provides additional diversity, enhancing Tor's ability to put control over your security and privacy back into your hands.
root@linux# gdebi omd-2013.08.27.mk_0.wheezy_amd64.debDeux modules proxy Apache sont nécessaires, vous devez activer ceux ci :
root@linux# a2enmod proxy_http
root@linux# /etc/init.d/apache2 restart
root@linux# rpm -Uvh http://download.fedora.redhat.com/pub/epel/5/i386/epel-release-5-4.noarch.rpmPour installer OMD utiliser la commande yum :
root@linux# yum install --nogpgcheck omd-0.42-0.42-centos55.14.x86_64.rpmL'option --nogpgcheck peut être utilisée si le package n'est pas signé.
root@VM-UBUNTU-01:~# netstat -rnAfficher les statistiques rapides des interfaces
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
0.0.0.0 10.250.0.10 0.0.0.0 UG 0 0 0 eth0
10.250.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
root@VM-UBUNTU-01:~# netstat -iAfficher les statistiques complètes des interfaces
Kernel Interface table
Iface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg
eth0 1500 0 5631321 0 143 0 2403793 0 0 0 BMRU
lo 65536 0 7752 0 0 0 7752 0 0 0 LRU
root@VM-UBUNTU-01:~# netstat -ieOn peut souligner que la commande "netstat -e" est équivalente à la commande "ifconfig -a".
Kernel Interface table
eth0 Link encap:Ethernet HWaddr 00:0c:29:e8:cc:d3
inet addr:10.250.0.150 Bcast:10.250.0.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fee8:ccd3/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:5631385 errors:0 dropped:143 overruns:0 frame:0
TX packets:2403806 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:3038943399 (3.0 GB) TX bytes:3907704626 (3.9 GB)
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:7752 errors:0 dropped:0 overruns:0 frame:0
TX packets:7752 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:704050 (704.0 KB) TX bytes:704050 (704.0 KB)
root@VM-UBUNTU-01:~# netstat -uta
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 *:ssh *:* LISTEN
tcp 0 0 localhost:mysql *:* LISTEN
tcp 0 0 10.250.0.150:ssh 10.250.0.50:40373 ESTABLISHED
tcp 0 0 10.250.0.150:ssh 10.250.0.50:46060 ESTABLISHED
tcp6 0 0 [::]:ssh [::]:* LISTEN
tcp6 0 0 [::]:http [::]:* LISTEN
|
ESTABLISHED:
SYN_SENT: SYN_RECV: FIN_WAIT1: FIN_WAIT2: TIME_WAIT: CLOSED: CLOSE_WAIT: LAST_ACK: LISTEN: CLOSING: UNKNOWN: |
La socket a une connexion établie.
La socket attend activement d'établir une connexion. Une requête de connexion a été reçue du réseau. La socket est fermée, et la connexion est en cours de terminaison. La connexion est fermée, et la socket attend une terminaison du distant. La socket attend le traitement de tous les paquets encore sur le réseau avant d'entreprendre la fermeture. La socket n'est pas utilisée. Le distant a arrêté, attendant la fermeture de la socket. Le distant termine, et la socket est fermée. Attente d'acquittement. La socket est à l'écoute de connexions entrantes. Ces sockets ne sont affichées que si le paramètre -a,--listening est fourni. Les deux prises sont arrêtées mais toutes les données locales n'ont pas encore été envoyées. L'état de la prise est inconnu. |
root@VM-UBUNTU-01:~# netstat -aute
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State User Inode
tcp 0 0 *:ssh *:* LISTEN root 9022
tcp 0 0 localhost:mysql *:* LISTEN mysql 2310050
tcp 0 0 10.250.0.150:ssh 10.250.0.50:40373 ESTABLISHED root 2686139
tcp 0 320 10.250.0.150:ssh 10.250.0.50:46060 ESTABLISHED root 2696343
tcp6 0 0 [::]:ssh [::]:* LISTEN root 9024
tcp6 0 0 [::]:http [::]:* LISTEN root 2311284
root@VM-UBUNTU-01:~# netstat -ltAfficher les statistiques par protocole
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 *:ssh *:* LISTEN
tcp 0 0 localhost:mysql *:* LISTEN
tcp6 0 0 [::]:ssh [::]:* LISTEN
tcp6 0 0 [::]:http [::]:* LISTEN
root@VM-UBUNTU-01:~# netstat -sAller plus loin?
Ip:
1778352 total packets received
0 forwarded
0 incoming packets discarded
1778351 incoming packets delivered
1244698 requests sent out
1727 outgoing packets dropped
Icmp:
3626 ICMP messages received
0 input ICMP message failed.
ICMP input histogram:
destination unreachable: 3626
3626 ICMP messages sent
0 ICMP messages failed
ICMP output histogram:
destination unreachable: 3626
IcmpMsg:
InType3: 3626
OutType3: 3626
Tcp:
4310 active connections openings
124 passive connection openings
0 failed connection attempts
75 connection resets received
2 connections established
1766668 segments received
2385158 segments send out
47 segments retransmited
0 bad segments received.
104 resets sent
Udp:
0 packets received
3626 packets to unknown port received.
0 packet receive errors
3628 packets sent
UdpLite:
TcpExt:
2 invalid SYN cookies received
1480 TCP sockets finished time wait in fast timer
7072 delayed acks sent
18 delayed acks further delayed because of locked socket
Quick ack mode was activated 24 times
33 packets directly queued to recvmsg prequeue.
4425586 bytes directly in process context from backlog
7126 bytes directly received in process context from prequeue
518714 packet headers predicted
2240 packets header predicted and directly queued to user
1076152 acknowledgments not containing data payload received
115565 predicted acknowledgments
21 times recovered from packet loss by selective acknowledgements
24 congestion windows recovered without slow start after partial ack
21 fast retransmits
25 other TCP timeouts
TCPLossProbes: 151
TCPLossProbeRecovery: 54
25 DSACKs sent for old packets
89 DSACKs received
40 connections reset due to early user close
TCPDSACKIgnoredNoUndo: 51
TCPSackShifted: 62
TCPSackMerged: 47
TCPSackShiftFallback: 68
TCPDeferAcceptDrop: 55
TCPRcvCoalesce: 181682
TCPOFOQueue: 189
TCPSpuriousRtxHostQueues: 31
IpExt:
InMcastPkts: 2
InBcastPkts: 4919
InOctets: -1516352654
OutOctets: -1698348110
InMcastOctets: 72
InBcastOctets: 1059047
InNoECTPkts: 3222497
root@VM-UBUNTU-01:~# netstat -pauntComment lire les résultats de la commande netstat, par colonnes :
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 820/sshd
tcp 0 0 127.0.0.1:3306 0.0.0.0:* LISTEN 26331/mysqld
tcp 0 0 10.250.0.150:22 10.250.0.50:40373 ESTABLISHED 19027/sshd: stanisl
tcp 0 0 10.250.0.150:22 10.250.0.50:46060 ESTABLISHED 19532/3
tcp6 0 0 :::22 :::* LISTEN 820/sshd
tcp6 0 0 :::80 :::* LISTEN 11762/apache2
GNU Screen is a software application that can be used to multiplex several virtual consoles, allowing a user to access multiple separate terminal sessions inside a single terminal window or remote terminal session. It is useful for dealing with multiple programs from a command line interface, and for separating programs from the Unix shell that started the program. (https://en.wikipedia.org/wiki/GNU_Screen)
# apt-get install screenOuvrir une session screen:
# screen -S download_ubuntu
# wget http://releases.ubuntu.com/15.10/ubuntu-15.10-server-amd64.isoLaisser courir le téléchargement
--2015-11-30 15:38:33-- http://releases.ubuntu.com/15.10/ubuntu-15.10-server-amd64.iso
Connecting to 10.49.64.5:8080... connected.
Proxy request sent, awaiting response... 200 OK
Length: 662700032 (632M) [application/x-iso9660-image]
Saving to: ‘ubuntu-15.10-server-amd64.iso’
0% [ ] 3 461 854 576KB/s eta 18m 29s
Taper simultanément [CTRL] + a puis d
Lister les sessions screen actives:
[detached from 5049.download_ubuntu]
# screen -ls
There are screens on:
5049.download_ubuntu (30/11/2015 15:38:01) (Detached)
5019.1 (30/11/2015 15:33:47) (Detached)
2 Sockets in /var/run/screen/S-root.
# screen -r 5049.download_ubuntu
# man screenhttps://www.gnu.org/software/screen/manual/screen.html
#!/bin/sh
HORODATAGE=`date +%s`
FICHIER="fichier-$HORODATAGE.txt"
echo "creation du fichier $FICHIER"
touch $FICHIER
echo "$HORODATAGE humainement parlant correspond à la date du `date -ud @$HORODATAGE`"
$ ./temps_t.sh
creation du fichier fichier-1448275999.txt
1448275999 humainement parlant correspond à la date du lundi 23 novembre 2015, 10:53:19 (UTC+0000)
