Checking for email server blacklisting

Trying to understand why mail is not being sent ? [For Sendmail] If your  tail -f /var/log/maillog logs are showing something like this: Aug 30 22:43:06 netman sendmail[8100]: starting daemon (8.14.4): SMTP+queueing@01:00:00 Aug 30 22:43:06 netman sm-msp-queue[8109]: starting daemon (8.14.4): queueing@01:00:00 Aug 30 22:43:11 netman sendmail[8102]: q7SIq1Kk011256: to=<>, ctladdr=<root@netman.lan> (0/0), delay=2+04:51:10, xdelay=00:00:05, mailer=esmtp, pri=3720580, [XX.125.142.26], […]

Creating a router on a CentOS 6 server

Assuming you want to NAT the network on eth1 and route the traffic to eth0 this is the spell: Create the forwarding rule: /sbin/iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE and then enable IP forwarding  echo “1” > /proc/sys/net/ipv4/ip_forward OR sysctl -w net.ipv4.ip_forward=1   Permanent setting using /etc/sysctl.conf If we want to make […]

Windows time stamping in batch files

Creating a time-stamp  in windows can be usful for the automated backups we all SHOULD be doing 🙂   pkzip c:\<source>\*.* c:\<target>\ ren C:\<target>\TempZip.Zip c:\<target>\TempZip_%date:~-4,4%%date:~-7,2%%date:~-10,   Or simply to create a directory for copying open files (Lawrence 🙂 ) set backdir=%date:~-4,4%%date:~-7,2%%date:~-10,2% mkdir %backdir% cd %backdir% etc..    

Allow remote SQL connection to Mysql from any host

Allowing the login of a user from any host in Mysql is simple: mysql> select host, user from mysql.user; +—————+——+ | host | user | +—————+——+ | | root | | localhost | root | | minimal01.lan | root | +—————+——+ 3 rows in set (0.00 sec) mysql> update mysql.user set host=’%’ where host=’′; […]

Enable grub menu UBUNTU

Enable grub menu: edit the /etc/default/grub  file and change the GRUB_HIDDEN_TIMEOUT=0 GRUB_HIDDEN_TIMEOUT_QUIET=true to GRUB_HIDDEN_TIMEOUT=10 GRUB_HIDDEN_TIMEOUT_QUIET=false Save and call: sudo update-grub from a terminal, and reboot.

Manually reset the state of an instance

If an instance gets stuck in an intermediate state (e.g., “deleting”), you can manually reset the state of an instance using the nova reset-state command. This will reset it to an error state, which you can then delete. For example: $ nova reset-state c6bbbf26-b40a-47e7-8d5c-eb17bf65c485 $ nova delete c6bbbf26-b40a-47e7-8d5c-eb17bf65c485 You can also use the –active to force the instance back […]