lxc broken after upgrade from linux-image-4.12.0-0.bpo.1-amd64 to linux-image-4.13.0-0.bpo.1-amd64

lxc containers no longer start after i’ve upgraded debian stretch server from 4.12 kernel from stretch-backports repository to 4.13 also from backports. symptoms in /var/log/syslog: that was resolved by creating /etc/systemd/network/99-default.link with: via this comment. then there was nothing interesting in syslog but the lxc guest still would not start – lxc-start -F -n serverName …

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btrfs and nfs dont play nicely together

i use ghettoVCB to take backups of vmware esxi 6.5 vms. data is copied to a nfs share hosted on Debian Linux. for over a year i used btrfs partition as an underlying datastore for the nfs share. and i just could not get it to work for backups which size larger than available RAM …

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opendkim failing to start after recent routine debian update

on 2017-10-12 i’ve done a routine apt-get update; apt-get upgrade on a debian stretch vm that, among other services, runs opendkim service that adds a digital signature in the headers of the outgoing mails. during the update i was asked weather to keep or replace the /etc/opendkim.conf; as usual in such cases i’ve answered no …

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“out of range” on drac console when booting debian stretch

i’ve installed debian stretch on an old dell poweredge 2950. after booting it i saw grub, few lines from kernel and then green screen with “out of range”: reboot, on the grub menu select “*Debian GNU/Linux”, press e, hilight a line with linux /boot/vmlinuz-4.9.0-3-amd64 root=/dev/sda1 ro quiet, add there vga=normal fb=false nomodeset and press ctrl+x …

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sphinxsearch reborn as manticoresearch?

for the past year number of commits in my favorite open source text-search server – the sphinxsearch project – has dropped to nearly 0. looks like in the meanwhile some of the old contributors moved to another project – manticoresearch. the website of the new project features two prominent supporters – craigslist and boardreader. fingers …

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unwanted wordpress trackback spam

today i’ve learned that disabling trackback in wordpress’s settings > discussion [ ] Allow link notifications from other blogs (pingbacks and trackbacks) on new articles is not enough. your old posts, created before the date when this check-box was un-ticked, will still allow trackback which might be spammy. solution? adjust the trackback setting on per-post …

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varying svn checkout times under virtualized windows server 2016

we’ve set up a new build server using Windows Server 2016 running under ESXi 6.5. few days later devs came back with a complain: full svn checkout time varies a lot – it takes between 1 and 8 minutes. steps taken that hopefully resolved the issue: disable the icon cache of tortoise svn, then eventually …

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posting a file from command line with CURL

i needed to write a .bat script for windows to upload a log file. quick and nasty hack.. on the sending end: looks straightforward, worked when i tested; but failed to upload in the production setup. on the http server/PHP i was getting: turned out that the log file was growing. curl at the beginning …

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extracting attachments from unix mail files

i log some of the messages passing by Postfix-based relay using always_bcc = bcc@somewhere.com in main.cf. Sometimes – to track spam or problems – i need to check content of the attachments. this comes handy if content is embedded inline i have to edit the file and replace or just add the 2nd part if …

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bind9 on debian jessie ignores -4 in /etc/default/bind9 and tries to make lookups via ipv6

while checking one of the servers running debian jessie i’ve noticed that logs are full of: strange… didn’t i put “-4” in the /etc/default/bind9 ages ago? apparently i did but ps shows that it was ignored: a bit of googling told me it’s a known problem with systemd [sic!] – the /etc/default/bind9 is ignored. workaround? …

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sphinx search 2.2.11 – column count does not match schema (expected 3, got 2)

i have a real-time sphinx that was configured in this way:\ it was updated using REPLACE INTO myrt VALUES(?,?)… until the day i’ve upgraded to 2.2.11. the update command started to give me: after a bit of investigation i’ve discovered that: with RT index it’s obligatory to have at least one attribute [not id], even …

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dlink DXS-1210-12TC – web interface hanging

i’ve made a mistake again and bought a ‘cheap’, smart-managed network switch. dlink DXS-1210-12TC with 12 10gbase-t ports. and i got punished nearly immediately – the web interface of the device would hang on me after few days of uptime. sometimes it wasn’t even possible to log in, other times – i could log in …

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“operator or administrator has refused the request (0x800710E0)” in the windows task scheduler

at work we have a Windows 2012 server [ more than one. sadly… ]. one of them had few nightly batch jobs started from the task scheduler. a certain task would fail occasionally and give us the “operator or administrator has refused the request (0x800710E0)” error. googling did not help much – it’s a server, …

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drac5 / 6 with latest java 1.8.73

new java – new problems. “Error when reading form SSL socket connection” showed again after the upgrade to new java follow the steps from the earlier post and edit those in the C:\Program Files (x86)\Java\jre1.8.0_73\lib\security\java.security: also: go to the Control panel > java in the General tab: Settings > Delete files – mark all the …

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Dell’s 10gbase-t network cards on Intel’s x540 chips

we’re upgrading few servers at work to have 10gbit/s connectivity. to keep things familiar i’ve decided to stick with [power hungry and latency-inducing] cat7 copper cabling and 10gbase-t. there are few dell poweredge r620 and r630 to be upgraded. currently those have proprietary broadcom-based daughter-cards with 4x 1000base-t ports. i preferred to replace them with …

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esxi 6.0: “create virtual machine snapshot” “a general system error occurred”

i’ve upgraded from esxi 5.5 to 6.0 a couple of servers. soon after i’ve discovered that ghettoVCB would fail on some of VMs while it worked fine on the others. i’ve started poking around and found out that for those VMs where backup failed i creation of snapshot would fail with the following error: while …

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“Waiting for TUN/TAP interface to come up” in OpenVPN logs under windows 10

i run windows 10 on one of the computers, it also has a ‘dial up’ openvpn – started from openvpn gui. it worked fine for a few days but then i started to see repeting in the logs and tunnel would not get up for 20-60 seconds. and sometimes even after that the right entries …

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