xiaomi robot vaccuum disassembly

i have 1st gen xiaomi mi robot vacuum cleaner. it’s been serving very well for the past 3 years. this video was very helpful with disassembly when i had to replace the main sucking motor fan: https://www.youtube.com/watch?v=wdDSBgJ1kRM i had to replace a fan and bought https://www.aliexpress.com/item/4000804127893.html instead of https://www.aliexpress.com/item/4000259186760.html ; not an exact fit but …

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letting dbeaver talk with manticoresearch

here’s what i did to get dbeaver 7.3.2 + oracle’s JDBC mysql-connector-java-8.0.17.jar work with manticoresearch 3.5.4: /etc/manticoresearch/manticore.conf, under searchd: in dbeaver – new connection using oracle’s JDBC driver as above, under data editor – set ResultFetchSize to 0 to prevent errors like this: when i initially tried to get it working with JDBC driver from …

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black hole, somewhere in the internet, swallowing UDP packets

UDP packets sent from specific source port, with public source IP address do not reach specific destination port of the public destination IP address. changing any of the parameters [ usually source port ] – fixes the issue. i’ve observed this phenomenon multiple times for long-running OpenVPN and Wireguard VPNs encapsulating encrypted traffic in UDP …

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let’s encrypt via proxy server under debian

i prefer to have strict DROP policy for the outgoing traffic from production servers. let’s encrypt API endpoint is behind Akamai’s CDN and IP address to which acme-v02.api.letsencrypt.org resolves changes frequently. i don’t like playing whack-a-mole every 3 months so i’ve: set up a squid-based proxy server that allows for filtering based on domain names: …

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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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Windows 10 client cannot anymore access public samba share that does not require any login

i’ve run into an issue where windows 10 desktop could not anymore access a simple samba share on a linux server; that linux server did not have any type of authorization put in place. Windows would randomly give errors ” might not have permission to use this network resource” or “Windows cannot access \\Server\ShareYou do …

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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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