=== coconut__ is now known as coconut [11:36] It looks like I have some kind of ddos attack to my DNS servers [11:37] both ubuntu bind9 servers keep segfaulting after many thousend of requests [11:37] see here: https://dpaste.org/SX29#L16 [11:37] maybe I can block the IP with fail2ban somehow? [11:37] BIND 9.16.1-Ubuntu (Stable Release) [11:41] Aison`: are you using the latest bind9 version: 1:9.16.1-0ubuntu2.2 [11:42] yes [11:44] Aison`: OK good. Could you run a tcpdump capture of the traffic leading to a crash? If you could attach it along with the crash dump to a LP bug, I'm sure it could help having the problem fixed [11:48] :( now it stopped crashing [11:48] https://bind9.readthedocs.io/en/v9_16_5/notes.html#notes-for-bind-9-16-5 show a few assertion failures were fixed since the 9.16.1 release [11:55] I can not reproduce the sefault [11:56] it's just "luck" when it happens [12:45] Aison`: IIRC, installing the -dbg package will allow the crash to be dumped through gdb, but not sure if everyhing is automatic [13:30] RoyK, there is not dbg for bind [13:31] sdeziel, how can I tcpdump the whole udp53 traffic to a file? I can not google it right now ;) [13:33] tshark tshark -f "udp and port 53" [13:34] without the first tshark ;) [13:34] tshark is the new tcpdump [13:35] Aison`: otherwise: tcpdump -w /tmp/dns.pcap -ni $iface port 53 [13:36] Aison`: DNS also happens on TCP/53 so I'd capture both [18:26] OK, so this is on Ubuntu 18.04, andone want to take a look and lend a hand with a syslog-ng issue ? https://pastebin.com/EV7km0QW\ [18:27] Page not found. [18:27] use paste.ubuntu.com :-D [18:28] it's https://pastebin.com/EV7km0QW [18:29] and it requires rather more syslog knowledge than I've got [18:32] oh i see, hit the enter+\ [18:34] hehe, yeah, I saw the contents just a few minutes earlier from another shared channel earlier and knew that it worked :) hehe [18:34] i'll remember that .. [19:50] just don't use pastebin dot com - it's a spmmer - there are several places that are better to use. I stick to paste.debian.net, but that's just me [19:58] ...fine whatever [19:58] I have never had an issue with pastebin [20:00] it's just that it sucks and it dumps ads on you if you mention it to a stranger [20:04] hello i'm still fighting with my ISC DHCP Server who tries to access LDAP for name resolving [20:05] sadly apparmor is blocking this call [20:05] Aison: pastebin your DENIED lines? [20:06] this is dmesg: [2946488.790491] audit: type=1400 audit(1597781143.428:28280): apparmor="DENIED" operation="connect" info="Failed name lookup - disconnected path" error=-13 profile="/usr/sbin/dhcpd" name="run/slapd-inetserv.socket" pid=1121070 comm="isc-worker0000" requested_mask="wr" denied_mask="wr" fsuid=110 ouid=0 [20:07] Aison: you'll need to add 'flags=(attach_disconnected)' to your profile, check /etc/apparmor.d/ for a few examples [20:07] here the profile from apparmor dhcp: https://paste.ubuntu.com/p/Gkv4jsxcjx/ [20:08] I added lines beginning at 29 [20:08] sarnold, ok [20:22] and dhcpd tries to access also /proc/sys/net/ipv4/ip_local_port_range? [20:26] sounds reasonable to me