DDoS attacks appear to have become increasingly more commonplace, and the other day the miscreants decided to target my Internet forum. I don't use CloudFlare or other third-party DDoS protection services since I try to avoid dependency on external services as much as possible. However, even an old CentOS7 server will have various tools available to protect against or mitigate such attacks. You just need to know how to use them! Here is the true story of how I fought and won!
How To Prevent #SSH Brute Force Attacks Using #Fail2ban In #Linux 🐧
https://ostechnix.com/prevent-ssh-brute-force-attacks-fail2ban-linux/
How To Prevent SSH Brute Force Attacks Using Fail2ban In Linux #python #macos #linuxsecurity #monitoring #bsd #ids #intrusiondetectionsoftware #fail2ban #intrusionpreventionsoftware #banhosts #ips #loganalyzer #security #opensource #linux #linuxadministration
https://ostechnix.com/prevent-ssh-brute-force-attacks-fail2ban-linux/
#Python #macOS #linuxsecurity #monitoring #BSD #ids #intrusiondetectionsoftware #fail2ban #intrusionpreventionsoftware #banhosts #ips #loganalyzer #security #OpenSource #Linux #Linuxadministration
Oops, banned my own IP address in #Cloudflare (#fail2ban working too well). Took a lot of monkey business to figure out how to unban myself, ha ha ha. #SysAdmin #fail
#cloudflare #fail2ban #sysadmin #fail
C'est bientôt la rentrée et l'école de ma grande commence à lui envoyer des mails... à la mauvaise adresse (mais sur le bon domaine).
En attendant de les prévenir pour corriger, j'ai ajouté un alias avec la coquille qui pointe vers la bonne boîte. Comme quoi, avoir la main sur son serveur et garder un œil sur ses logs, ça peut servir...
#loki #grafana #selfhosting #autoHebergement #log #mail #fail2ban
#loki #grafana #selfhosting #autohebergement #log #mail #fail2ban
Fail2ban sshd rule is active but not working! #ssh #authentication #fail2ban
#SSH #authentication #fail2ban
I assume you grow exclusion tables from the #fail2ban feedback; what methods do you use?
Ein neuer Forumbeitrag: https://linux-nerds.org/topic/1494/crowdsec-ein-fail2ban-ersatz 1494/crowdsec-ein-fail2ban-ersatz #crowdsec #linux #fail2ban
@MartinGuay ufw and fail2ban is an epic combo.
If you’re using caddy remember to add a #caddy conf to #fail2ban
https://muetsch.io/how-to-integrate-caddy-with-fail2ban.html
@marwil #PacketFence maybe? https://www.packetfence.org/ I've installed it, but not done much with it yet, I think I need to sort my VLANs out first :/
#fail2ban (https://en.wikipedia.org/wiki/Fail2ban) if it's not already on your OS.
I've wanted to run a honeypot for some time, but when I last looked a lot of development had stopped for the FOSS ones.
@selea layer4 (syn flood, file descriptor exhaustion): mostly a non issue nowadays because ram is cheap enough.
tls: rate limiting works (eg with #haproxy ) or techniques along the #fail2ban idea : if an ip hits you too hard, filter it efficiently in the kernel
http: here my best recommendations are all based around #varnishcache because i work on it, but alternatives do exist. i will focus on what i know to be most helpful. 🧵
#haproxy #fail2ban #varnishcache
Am 03.08.2023 ist wieder Online-Vortrag in der #TroLUG: "#CrowdSec - not your average #fail2ban replacement" von Viktoria Rei Bauer. Um 19:00 gehts los. Einwahlinfos auf https://trolug.de/termine.html
Y aurait-t-il des connaisseurs de #Fail2ban ici ?
Aucun de mes filtres ne semblent fonctionner sous Debian, notamment pour #nextcloud et sshd
Si quelqu'un a une idée sur le pourquoi sur #linux #debian 12 fraîchement installée #fail2ban ne passe aucune règle à nftables (#iptables testée aussi) alors que fail2ban-client montre bien que les IP sont bannies, je prends !
Une erreur ou incompréhension de débutant assurément, n'hésitez pas à me répondre en mode neuneu ! Merci ! (Je suis revenu à rsyslog car c'était impossible de matcher les regex des filtres avec les journaux systemd)
#linux #debian #fail2ban #iptables
Hoy he sacado un ratillo y he hecho un par de mejoras en el servidor bastante interesantes.
La primera es que he instalado ElasticSearch para tener búsqueda de texto completo. Es cierto que es una búsqueda muy limitada disponible únicamente para mis propios posts o aquéllos que haya marcado como favorito/boost/marcador pero aún así me sigue pareciendo útil. Además las búsquedas de cuentas o hashtags ahora parecen también ir más rápido. La instalación es bastante sencilla aunque ha exigido un poco de tuneo por la poca RAM que tiene mi VPS. Por ahora parece que aguanta bien de memoria y lo mantendré. Si empieza a consumir demasiados recursos me tendré que plantear cambiar de servidor a otro más potente (pereza máxima) o directamente quitarlo y será bonito mientras dure.
La segunda es más a nivel de tripas. He estado cacharreando un poco con el fail2ban porque he visto en los logs del nginx que algún bot estaba dando por saco de vez en cuando. Así que a la mínima que hagas cosas raras te vas a castigado un par de horitas al rincón de iptables. En lo que va de día la regla ya se ha activado más de 200 veces con un total de 23 bloqueos.
#mastoadmin #fail2ban #elastic
#mastoadmin #fail2ban #elastic
Just spent an hour debugging why #fail2ban won't hit a line in #postfix logs where the client's hostname can't be resolved.
Turned out that fail2ban's regex is too restrictive, requiring "4.7.1" in postfix's logfile (whatever that means), but postfix actually puts "4.7.25" in there. I changed the regex from "4\.7\.1" to "4\.7\.(1|25)" and it works now.
#fail2ban #postfix #linux #spam #servicetoot