While going though my logs I found that BIND9 on Debian version 5.x is giving a warning which read as follows:
max open files (1024) is smaller than max sockets (4096)
How do I fix this problem?
The “open files is smaller than max sockets” problem is kernel bug which is already fixed in 2.6.28. Linux kernel returns EPERM when RLIMIT_NOFILE is set to RLIM_INFINITY. To fix this issue update your Linux kernel using yum or apt-get command.
# yum update
OR
# apt-get update
# apt-get upgrade
Reboot the server. Verify error is not reported after boot:
# tail -f /var/log/messages
See kernel bug # 461458 and 515673 for more information.
🐧 If you liked this page, please support my work on Patreon or with a donation.
🐧 Get the latest tutorials on SysAdmin, Linux/Unix, Open Source/DevOps topics:
🐧 Get the latest tutorials on SysAdmin, Linux/Unix, Open Source/DevOps topics:
- RSS feed or Weekly email newsletter
- Share on Twitter • Facebook • 9 comments... add one ↓
UP NEXT
| Category | List of Unix and Linux commands |
|---|---|
| File Management | cat |
| Firewall | Alpine Awall • CentOS 8 • OpenSUSE • RHEL 8 • Ubuntu 16.04 • Ubuntu 18.04 • Ubuntu 20.04 |
| Network Utilities | dig • host • ip • nmap |
| OpenVPN | CentOS 7 • CentOS 8 • Debian 10 • Debian 8/9 • Ubuntu 18.04 • Ubuntu 20.04 |
| Package Manager | apk • apt |
| Processes Management | bg • chroot • cron • disown • fg • jobs • killall • kill • pidof • pstree • pwdx • time |
| Searching | grep • whereis • which |
| User Information | groups • id • lastcomm • last • lid/libuser-lid • logname • members • users • whoami • who • w |
| WireGuard VPN | Alpine • CentOS 8 • Debian 10 • Firewall • Ubuntu 20.04 |
Soultion? ;-)
Thanks for the heads up.
how to fix on debian lenny 5.0 ( 2.6.26-2-686):
# vim /etc/default/bind9
add “-S 1024” to “OPTIONS” line:
restart bind:
# /etc/init.d/bind9 restart
check for errors:
# cat /var/log/syslog
ooops :)
# vim /etc/default/bind9
add “-S 1024″ to “OPTIONS” line:
# run resolvconf?
RESOLVCONF=yes
# startup options for the server
OPTIONS="-u bind -S 1024"
how to fix the error in freebsd?
sysctl kern.maxfilesperproc=4096
There’s another way of fixing it on Linux:
At the beginning of the “start” section of /etc/init.d/bind9 add i.e.:
ulimit -HSn 8192
so you have some extra, spare file descriptors for the whole process,
and then restart the bind using:
# /etc/init.d/bind9 restart
and voila, log reads:
[…]
named[19060]: using up to 4096 sockets
[…]
The preceding “ulimit -HSn 8192” command might better go in /etc/default/bind9 on debian to keep package updates (ie. changed config files) a little smoother.
If you are using Centos or redhat, edit /etc/sysconfig/named and at the bottom, at,
OPTIONS=”-4 -S 1024″
It think the author’s claim of upgrading the kernel it’s false and can be dangers. I got a vmware application runnning on the host, upgrading the kernel can simply break it