fighting a false-positive flagging by multiple antivirus vendors

recently i woke up to this: “Hi, some of our employees are using your application. This morning they have received an upgrade notification (in yellow banner) to get the latest version of your app. Our anti-virus/malware has triggered on your module called “somefile.exe” detected at risk being a “Trojan.Gen.MBT “. below few resources that i’ve …

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bridging lan segments across untrusted links

we’ve run out of the office space in one of the locations. in short term it was not possible to find a suitable and large enough place to rent so we had to split and relocate some of the staff to another building few kilometers away. it’s possible that we’ll shuffle people and servers between …

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multi-master mysql replication with servers on 3 different continents

at work i’m using mysql replication quite extensively. first it was a straightforward one-way replication that has been rock-solid for us since 2009. in 2012, for another type of data, we’ve started using master-master setup. initially the servers were in different European countries, eventually the secondary site was moved to North America while primary one …

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bridging two physical interfaces of esxi server

my colleagues got into an unpleasant situation where one of two dedicated servers, running vmware esxi 6.0, rented from a datacenter lost its network connectivity. the datacenter/internet-facing interface is down, hours later, during regular working day, the hosting provider did not react and resolve the problem. maybe the network card died, maybe switch port misbehaves …

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ghettoVCB failing randomly on larger VMs

at work we’re using happily to back up and restore VMWare ESXi VMs. since a few weeks we’ve started to experience occasional failures of backups, only for one – larger VMs. in the logs produced in /tmp/ghettoVCB-2017-04-xxx.log we got: or after some head scratching, watching at iostat -x 1 and ifstat -b 1 -i …

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simplistic gatekeeper limiting access to apache2-based proxy

i had to expose some web-based application hosted on a windows server to the internet. i don’t put too much trust in the developers of that particular application so i did not want to make it reachable from the public internet. while i could not use ip address based whitelist i could count on the …

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tuning spmassasin to treat more harshly mails with forged sender’s address claiming to come from us

once in a while we get e-mails with spoofed sender’s address claiming to come from this can fool some of our users; outlook displaying an image of sender solely based on the From: field does not help here. some of those messages have different Return-Path pointing to, other have it also pointing to …

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i’ve spent two weeks traveling around Tenerifa with my parents. we’ve seen a bit of the commercial-heavy south near Los Cristianos, rocky west coast in Los Gigantes, semi-rural areas of Icod de Vinos, a bit of Puerto de la Cruz and post-volcanic Teide and Puerto de Guimar. our hiking routes – below.

10 days in Albania

i’ve spent nearly two weeks traveling around Albania. i’ve started and ended the journey on a Greek island – Corfu [ i could not find any reasonably-priced flight from Berlin to Tirana ] and from there travelled with a ferry to Sarandë.

Chumphon, Hua Hin

on my way from Koh Tao to Bangkok i’ve stayed for one night at Chumphon and then Hua Hin. the first one was totally not-touristy, second – quite opposite; i’m glad that i decided not to rush towards Thailand’s capital and visited both.