raspberry pi as a serial console terminal
i’ve bricked a cheap home router. i’ve installed a beta of dd-wrt firmware which did not work. raspberry pi gave me serial connection to it.
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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MySQL on BTRFS?
i’ve been running a set of production MySQL databases on BTRFS since April 2016. BTRFS is not exactly known for its stellar performance when hosting databases or images of virtual machines due to its COW nature. why would i do it then? to have data snapshots and be able to ‘go back in time’ quickly …
bridge on vlans on active-backup bonding under debian stretch
i use this setup for few lxc servers. bonding provides me layer2 failover based on arp probes [ so it’ll work even if switch link stays up yet forwarding fails the mechanism will kick in ]. this is continuation of an earlier post, this time under debian stretch
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 ghettoVCB.sh 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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2 hikes in Hong Kong
i was in HK again; just for a week, but there was enough time during the weekend to hike again in the wildness. High Junk Peak at first i did not enjoy this route at all – just after living the last buildings behind: there was ~25 min of walking up the narrow concrete stairs …
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 @ourorg.com. 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 @someotherscammy.site, other have it also pointing to …
Tenerifa
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.
audible / drm
i’ve made a mistake of buying an audiobook from audible.com. before doing it i’ve briefly checked if the file will be provided in mp3; according to audible.com/sh yes. in reality – no.
mounting partitions from within of the vmware’s .vmdk file
i’m taking backups of vmware esxi vms weekly using ghettovcb. it has been working greatly for many years. once in a while i need to recover a particular file from particular backup. there’s quicker way than just restoring the whole vm!
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.
audit/access logs in samba
i’ve ‘convinced’ my samba running under debian wheezy/jessie to provide me access audit logs without being too verbose. here’s how.
Taling Chan floating market, Bangkok hike
i stayed in Bangkok for 3 nights. i took one-day trip to Ayutthaya and have spent rest of the time hiking around. the longest hike i took was to Taling Chan floating market. as in many other cases it was more about the way there and back than the destination itself.
Ayutthaya
as in 2012 i’ve done a one-day trip to Ayutthaya. it was very much worth repeating and getting away from noisy Bangkok.
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.
hiking on Koh Tao
i took a ferry from Koh Samui to Koh Tao and stayed there for 2 nights. the island was quite touristy but still worth visiting. i looked at the map and thought to myself.. if there’s a route coming from the west and another one from the east – there surely must be some path …
hiking on Koh Samui
during my recent trip to Thailand i’ve spent 4 days at the Koh Samui island. i’ve stayed in the southern part – near Baan Hua Thanon – fisherman village with quite obvious Muslim influence. the choice was great – area was not very touristy and a great starting point for hikes.