Tag: linux

Linux performance tidbits

Netflix originated: Linux Performance Analysis in 60,000 Milliseconds Netflix at Velocity 2015: Linux Performance Tools Brendan Gregg’s Linux Performance Ubuntu: Disk performance Redhat: Red Hat Enterprise Linux 6 Performance Tuning Guide Red Hat Enterprise Linux 7 Performance Tuning Guide

YASPI

Case: yum fails: http://yum.puppetlabs.com/el/6/dependencies/x86_64/repodata/repomd.xml: [Errno 14] PYCURL ERROR 7 – “Failed to connect to 2600:3c00::f03c:91ff:fe69:6bf0: Network is unreachable” in a machine which doesn’t have IPv6 connectivity Solution: Since connections go through proxy, define it to respective repo config Root cause:…

Federated VoIP

Noted that Fedora 19 Alpha has a feature called federated VoIP, debian has also described their unified communications opentelecoms.org has description about federated VoIP here – clips – The vision is true peer-to-peer VoIP, with no central point of control.…

Simple ip6tables rules

*filter :INPUT ACCEPT [0:0] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [0:0] -A INPUT -m state –state RELATED,ESTABLISHED -j ACCEPT -A INPUT -p tcp -m tcp –dport 80 -j ACCEPT -A INPUT -p tcp -m tcp –dport 443 -j ACCEPT -A INPUT…

suhosin error with cacti

Problem: Debian squeeze, suhosin and cacti interworking issue Symptoms: following entries in syslog May 25 09:54:02 machine suhosin[12340]: ALERT – script tried to increase memory_limit to 536870912 bytes which is above the allowed value (attacker ‘REMOTE_ADDR not set’, file ‘/usr/share/cacti/site/poller.php’,…