intellij freezing on startup + putty routinely failing to bind to ports used for ssh tunneling

for the past few weeks i was plagued by putty randomly failing to bind to ports used for ssh tunneling giving me in its log “forwarding failed: Network error: Permission denied” today my intellij failed to launch – it was freezing on the splash screen, C:\Users\xxxxxxxxxxxx\AppData\Local\JetBrains\IdeaIC2021.2\log\log.log had: that brought me to https://youtrack.jetbrains.com/issue/IDEA-238995 and workaroudn described …

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crude way to restore postgresql database dump to table with a different name

i needed to restore specific table, backed up via pg_dump, to the same database / schema but under different name. that’s what i’ve done pv dump.zstd|pzstd -dc – |sed ‘s/name_of_original_table/name_of_renamed_table/g’|su – postgres -c ‘psql dbname’ this only works if all constrains / indices have in their name name of the original table.

20x performance difference between two VMs running the same version of Elastic opendistro

i’ve just spent way too much time trying to figure out why the same query run on one VM with elastic 0.1s while on another – 2s. both VMs were running on the same physical server, had the same amount of cores allocated. i’ve finally found it – there was a tiny difference in amount …

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ClickHouse – dictionary with string keys

i wanted to create a clickhouse dictionary that used String as a key, not an int. docs mention here: “A composite key can consist of a single element. This makes it possible to use a string as the key, for instance”. I’ve been trying this and failed few times. creation worked but i could not …

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suddenly in-kernel communication between lxc containers gets erratic

we’re using LXC containers to host multiple workloads on the same physical servers. e.g. few instances of database servers running side-by-side. once in a while we end up with strange situation where tcp connections between containers running on the same physical server get torn down abruptly. in our case – this manifested e.g. by those …

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apache2 – redirect from http to https with some source-ip-based exceptions

i was migrating a server from http to https. while header-based redirect worked for most of the clients, for some – i had to allow for a transition period where some configuration / code had to be adjusted. here’s the config that responds with 302 redir to most of the http requests, but for those …

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changing source url of the svn repository replica

i have bunch of svn read-only replicas. they were created using: replication [ fetching of earlier not downloaded revisions ] is done via: to check from which url my replica repo fetches updates: to change it – run: that’s it – next execution of svnsync will fetch the data from the new origin url based …

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“Verify your Kindle document” for pdfs self-mailed to my kindle

whenever i travel i like to use kindle for reading some articles that i’ve earlier collected. for collecting i use a simple PHP script with rich text editor that allows me to copy & paste content and then mail it to my kindle address. recently i’ve started getting requests from Amazon to approve each document …

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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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supermicro server getting stuck on “loading initial ramdisk”

i had a quite puzzling moment today when a server refused to boot up after routine maintenance. order of events: datacenter technician has taken server down and added Mellanox 25Gbit network card server booted up cleanly with Debian Buster and aged kernel 4.19.0-6 i’ve rebooted the server again and changed cpu performance settings in bios …

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supermicro IPMI – mounting iso image via samba

reminder for my self in case i need to do it again, relevant for X11DDW-NT and likely – other their platforms: log-in to the IPMI web interface, go to virtual media > CD-ROM image, provide: share host – ip or hostname of samba server. for instance: 10.1.2.3 paht to image – backlash share name backslash …

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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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