• Linux wlan0 check all wireless clients


    iw dev wlan0 station dump This is very useful because it is helpful if you are running something like hostapd and need to see the signal strength and negotiated connection speed. Station ff:ff:ff:ff:ff:ff (on wlan0) inactive time: 16309 ms rx bytes: 25451 rx packets: 325 tx bytes: 44381 tx packets: 159 tx retries: 0 tx failed: 0 signal: -72 [-72] dBm signal avg: -72 [-72] dBm........
  • How To Create Apache htpasswd file


    This just simply outputs what you need a username and password that can be used to authenticate from .htaccess htpasswd -nb user password user:Gnb6uE9Lp4gt2 If you want to write it straight to a file htpasswd -cb /tmp/somefile.pw user password How To Use This In .htaccess AuthUserFile /tmp/somefile.pw AuthName GetLost!! AuthType B........
  • l2tp ipsec VPN Error Sep 12 18:16:25 vps pluto[7299]: ERROR: asynchronous network error report on eth0 (sport=500) for message to 192.5.6.2 port 20640, complainant 192.5.6.2: Connection refused [errno 111, origin ICMP type 3 code 3 (not authenticated


    Sep 12 18:16:25 vps pluto[7299]: ERROR: asynchronous network error report on eth0 (sport=500) for message to 192.5.6.2 port 20640, complainant 192.5.6.2: Connection refused [errno 111, origin ICMP type 3 code 3 (not authenticated)] Some say changing the "leftprotoport=17/%any" will fix this but I have not found this to be the case. Essentially it means at least one end is blocking the ipsec packets. Sometimes the %any allows an alt........
  • Postfix how to secure outgoing authenticated e-mails for privacy and hide the IP address, mailer and other things


    The most common solution is to use the /etc/postfix/header_checks but this is a big problem. Why is header_checks a problem? Because it does it to all mail whether incoming or outgoing and whether authenticated or not. We of course want as much header information for incoming as we can get for many reasons but many organizations want to secure and make their mail clients as secure as possible. I adapted this solution to the client's custom config, they are configur........
  • Asterisk iptables block bruteforce attacks howto with fail2ban


    yum -y install fail2ban vi /etc/fail2ban/jail.conf [asterisk-tcp] enabled = true filter = asterisk action = iptables-multiport[name=asterisk-tcp, port="5060,5061", protocol=tcp] sendmail-whois[name=Asterisk, dest=you@example.com, sender=fail2ban@example.com] logpath = /var/log/asterisk/messages maxret........
  • LOG: MAIN PANIC failed to expand condition "${if eq {$authenticated_id}{}{0}{${if eq {$sender_address}{$local_part@$domain}{0}{${if match{$received_protocol}{N^e?smtps?a$N}{${perl{checkbx_autowhitelist}{$authenticated_id}}}{${if eq{$received_prot


    I experienced this with CPanel's Exim after an auto-update (a Google of this error produces lots of complaints with few clear solutions). In this case I'll put the solution at the top. Run /scripts/buildeximconf to rebuild the Exim config and it should be fine after that. mail -vs "from test" user@dest.com < .bash_history LOG: MAIN cwd=/root 4 args: send-mail -i -v user@dest.com LOG: MAIN &........
  • Postfix Enable SSL/TLS with your certificate


    Create Cert & Key: openssl req -new -x509 -nodes -days 1530 -out server.crt -keyout server.key mkdir /etc/mailssl chmod 700 /etc/mailssl cp server.* /etc/mailssl Postfix SSL config Edit /etc/postfix/main.cf: #SSL stuff smtpd_tls_cert_file = /etc/mailssl/server.crt smtpd_tls_key_file = /etc/mailssl/server.key To make smtps w........
  • Installing Webmin & Enabling SSL


    Webmin Setup Centos 5: wget http://downloads.sourceforge.net/project/webadmin/webmin/1.530/webmin-1.530-1.noarch.rpm?r=http%3A%2F%2Fwww.webmin.com%2Fstandard.html&ts=1294339690&use_mirror=surfnet [1] 24229 [2] 24230 [root@host ~]# --2011-01-06 21:48:20-- http://downloads.sourceforge.net/project/webadmin/webmin/1.530/webmin-1.530-1.noarch.rpm?r=http%3A%2F%2Fwww.webmin.com%2Fstandard.html Resolving downloads.sourceforge.net... 216.34.181.........
  • MySQL Restoring And Dumping/Backing UP MySQL Data/Tables/Databases


    Backing MySQL Databases Backing Up/Dumping All Mysql Databases To A Single File mysqldump --all-databases -u admin -p > allmysqldatabases.sql The "-all-databases" clause is pretty obvious isn't it? It means that it will backup all databases. The "-u admin" means login using the user "admin", if you h........
  • Samba SMB Error - Server not using user level security and no password supplied. tree connect failed: NT_STATUS_WRONG_PASSWORD


    Server not using user level security and no password supplied. tree connect failed: NT_STATUS_WRONG_PASSWORD That happens when trying to use smbclient to connect to a share. The weird thing is that I can authnenticate just fine from Windows XP. It is partially my mistake, I forgot this share does have a password. I've tried authenticating with the correct user and also with "Guest" because this works in Windows. In Linux I ........
  • Viewing and Connecting to an SMB Samba Share on Windows/Linux/Unix


    This will give you the basic info needed to browse and connect to Samba shares from the command line. From the GUI of Gnome or KDE etc, it is pretty standard and straight forward. However, I've found very little guides on how to do it from the command line and if you're like me, a nerd who prefers command line for its simplicity and for remote use, this is the way to go. First get a list of all the Samba/SMB shares on the target. smbclient -L hostname........
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