When I was trying to update packages on one host I’ve stuck with yum hung on update. I run strace and see: strace -p 43734 Process 43734 attached - interrupt to quit futex(0x807c938, FUTEX_WAIT, 1, NULL <unfinished ...> Process 43734 detached It looks like yum database was corrupted, to repair this run: rm -f /var/lib/rpm/__db* rpm --rebuilddb yum clean all yum update Instead rm on db-files you could use gzip to have backup of these files.

I’ve few Nagios checks that require root privileges but running nrpe as root user is not acceptable. I prefer to use sudo for only these few commands. Run visudo and coment out this line: #Defaults requiretty This change is crucial to get scripts working. Then add at the end of file: %nrpe ALL=(ALL) NOPASSWD: /usr/lib64/nagios/plugins/ I’ve used nrpe group, but you have to add exactly group that your nrpe process uses. ...

After reading some SEO stuff I wanted to add some meta tags to my WordPress blog. I found this site: codex.wordpress.org/Meta_Tags_in_WordPress  external link . So WordPress thinks that it’s not necessary to have this meta tags any more… But I want it! 😃 Next funny thing is how they suggest to add meta tags: copy header.php - what about theme updates? ...

Let say you have MediaWiki installation but you lost admin credentials. If you have other account or if you could create one without any rights we’re in home 😉 We have few options to do this. Reset admin password We have to connect to database and use this SQL: UPDATE `user` SET user_password = CONCAT( SUBSTRING(user_password, 1, 3), SUBSTRING(MD5(user_name), 1, 8), ':', MD5(CONCAT(SUBSTRING(MD5(user_name), 1, 8), '-', MD5('new password')))) WHERE user_name = 'Admin'; Just replace Admin with your username and new password with your password. ...

I need to check memory usage of memcached server so I used: echo stats | nc 127.0.0.1 11211 STAT pid 2743 STAT uptime 263 STAT time 1395438951 STAT version 1.4.13 STAT pointer_size 64 STAT rusage_user 0.482926 STAT rusage_system 2.675593 STAT curr_items 8667 STAT total_items 10742 STAT bytes 23802513 STAT curr_connections 296 STAT total_connections 399 STAT connection_structures 297 STAT cmd_flush 0 STAT cmd_get 52578 STAT cmd_set 10792 STAT get_hits 28692 STAT get_misses 23886 STAT evictions 0 STAT bytes_read 35984361 STAT bytes_written 192647437 STAT limit_maxbytes 536870912 STAT threads 2 STAT accepting_conns 1 STAT listen_disabled_num 0 STAT replication MASTER STAT repcached_qi_free 8189 STAT repcached_wdata 0 STAT repcached_wsize 1026048 END For me, bytes value was important but you could find more about all statistics here  external link .

I have development server with postfix - I wanted to allow outbound traffic to one domain but cut off all the rest. I definitely do not want that test mail or any debug info goes to service users. I have to add something like that to /etc/postfix/transport: allowed.domain.com : * discard: Then run: postmap /etc/postfix/transport At end, add these to /etc/postfix/main.cf: transport_maps = hash:/etc/postfix/transport Reload postfix: postfix reload Test if it works: ...

In recent Ansible update to 1.5 version there is really nice feature ssh pipelining. This option is serious alternative to accelerated mode. Just add to you config file (ex. ~/.ansible.cfg): [ssh_connection] pipelining=True Now run any playbook - you will see the difference 😄 Source (and extended info about): http://blog.ansibleworks.com/2014/01/15/ssh-connection-upgrades-coming-in-ansible-1-5/  external link

To najlepszy przepis na chrusty jaki znam - wychodzą bardzo kruche i delikatne. Składniki 4 zółtka, 4 łyżki wina białego lub czerwonego, 4 łyżki mąki. Sposób przygotowania Wszystkie składniki wymieszać i wyrobić. Ciasto powinno być mniej wiecej takie jak na pierogi. Bić pałką/wałkiem, składać na pół i tak kilka razy przez ok 5 minut. Potem ciasto rozwałkować bardzo cieniutko i wykrawać chrusty, małe bo mocno rosną. Następnie wrzucać na rozgrzany olej/smalec. ...

I had quite simple task - compare two lists of hosts and check if hosts from first one are also on the second one. I started with diff: diff -u biglist.txt hosts_to_check.txt | grep -E "^\+" It was fine but output needs some filtering to get what I want. I’ve found another example with grep: grep -Fxv -f biglist.txt hosts_to_check.txt | sort -n This will search for all lines in hosts_to_check.txt which don’t match any line in biglist.txt. So after this I’ve got list of hosts that I have to check. That’s exactly what I need 😄

Learn how to change the default WSUS port from 8530 to 80 on Windows Server 2012, ensuring compatibility with older configurations and resolving IPv6-only issues.