• SSH cannot connect to old servers/devices/switches/routers/Cisco/Juniper Unable to negotiate with 192.168.20.2 port 22: no matching key exchange method found. Their offer: diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hell


    A lot of older devices either support telnet or very old SSH keyx algorithms which are insecure and disabled by all newer/modern SSH clients for security reasons. However, sometimes you may be on a LAN via VPNor some other secured network or for whatever reason, absolutely, need to connect to this device and sometimes old/embedded devices may not be possible to update to a newer SSH server. If you run into this you may be using a modern/newer SSH client and get thi........
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    pip install PIL ERROR: Could not find a version that satisfies the requirement PIL (from versions: none) ERROR: No matching distribution found for PIL The import name is PILbut the actual pip package is called "Pillow" pip install Pillow........
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    sudo pip3 install python-docx [sudo] password for : Downloading/unpacking python-docx Downloading python-docx-0.8.10.tar.gz (5.5MB): 5.5MB downloaded Running setup.py (path:/tmp/pip_build_root/python-docx/setup.py) egg_info for package python-docx no previously-included directories found matching 'docs/.build' warning: no previously-included files matching '.DS_Store' foun........
  • bash if statement with wildcard string matching


    In this case if fullurl started with http://www. then it is a match Note that you CANNOT put quotes around it or it becomes a literal match which will not work as intended in the bash script example below. if [[ $fullurl == http://www.* ]]; then echo "do something" fi Another example say we want to delete every file or dir in a path except sometihng that starts with "hellothere": for file in `l........
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    So I have a domain "testdomain.com". Inside test domain.com's root is the following .htaccess: Options +FollowSymLinks -Indexes ErrorDocument 403 /launch/index.html Order Deny,Allow Deny From All Allow From 192.168.1.2 When you visit anything other than root things work fine. Eg. if you visit http://testdomain.com/somedirfile.html It will show the right error in /launch/........
  • Unable to negotiate with 192.168.1.99 port 22: no matching host key type found. Their offer: ssh-dss Solution


    ssh rtt@192.168.1.199 Unable to negotiate with 192.168.1.99 port 22: no matching host key type found. Their offer: ssh-dss It looks like the DSS option is not considered secure so when connecting from newer Linux systems to an older one you will get the above error. It can be fixed (but you should consider upgrading your SSH daemon): ssh -oHostKeyAlgorithms=+ssh-dss rtt@192.168.1.199........
  • Migrate Centos 7 from Single HDD to mdadm RAID 10 array:


    Done on Centos 7.3 very important as clearly based on older guides it was a lot easier and more simpler! Hint do not use grub2-install! If you have trouble booting after this check this CentOS mdadm RAID booting/fixing guide. One huge caveat if you are an oldschool user or sysadmin who has avoided UEFIbooting The nor........
  • Centos 7 Cudaminer Nvidia setup guide


    I am using a GTX 1060 but replace the download for the driver with the correct/current version for your particular card by visiting: http://www.nvidia.com/Download/index.aspx?lang=en-us yum install automake curl openssl-devel libcurl-devel gcc gcc-c++ yum -y install kernel-devel-`uname -r` yum -y install unzip #the........
  • ssh session and port forward or reverse port matching or assocation howto


    Use netstat with the -anpe option. The e option shows the inodes and I do not know if it will always work or if it was by fluke but I was dealing with dozens of SSHsessions and needed to know which session was related to which forward (the PIDs of the SSHand SSHD did not match etc...) Notice the "59560675" and "59560762" those are almost identical, if you find two sets that are nearly identical except for the last 3 digits they may match (in my ca........
  • bash script how to do wildcard string comparisons or matching


    This is a feature that works very well in bash and is easy to do: *Remember you need the double brackets for this specific test even though a normal if would not require them variable="hi there" if [[ "$variable" = hi* ]]; then echo "yes it contains hi" fi........
  • drbd won't sync 8.3.13 on OpenVZ kernel


    I used the matching 8.3.13 utilities and it didn't work but strangely the newer 8.3.16 which makes DRBD complain works just fine. GIT-hash: 83ca112086600faacab2f157bc5a9324f7bd7f77 build by root@sighted, 2012-10-09 12:47:51  0: cs:SyncSource ro:Secondary/Primary ds:UpToDate/Inconsistent A r-----     ns:0 nr:0 dw:0 dr:0 al:0 bm:0 lo:0 pe:0 ua:0 ap:0 ep:1 wo:b oos:5236960   &am........
  • 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........
  • mdadm: /dev/sdb1 not large enough to join array solution


    mdadm --manage /dev/md1 --add /dev/sdb1 mdadm: metadata format 00.90 unknown, ignored. mdadm: metadata format 00.90 unknown, ignored. mdadm: metadata format 00.90 unknown, ignored. mdadm: /dev/sdb1 not large enough to join array md1's first primary member /dev/sda3 has 57394 cylinders while the /dev/sdb1 has 57393 (1 less cylinder) which is why it won't work. fdisk -l /dev/sda3 Disk /dev/sda3: 47........
  • Toms Hardware Hard Drive Comparison/Hitachi Deskstar 1TB


    I bought the 1TB Deskstar C revision recently at just $49 each and put them in RAID 1for my Desktop. Look at how close the old Deskstar 1TB comes to matching the performance of the mor expensive Samsung and WD's? This is phenomal, I can't believe the performance I've gotten out of these cheap drives. http://www.tomshardware.com/reviews/hitachi-western-digital-terabyte,2017-6.html........
  • 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.........
  • sed is great for pattern matching or retrieving lines


    sed is great for pattern matching or retrieving linesHere is a cool example Say you type df: The output would be something like: [quote:3bb8d51437]Filesystem 1k-blocks Used Available Use% Mounted on /dev/hda2 1712432 1206664 418780 75% / /dev/hda1 31201 10505 19085 36% /boot none 30932 0 30932 0% /dev/shm [/quote:3bb8d51........
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