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Link Aggregation – a solução para não usar 10GbE ainda.

Não é de hoje a busca por links de grande capacidade, principalmente por Provedores de Internet. Lembro da época que interfaces de rede Gigabit eram muito caras e vivíamos com redes 10/100. O provedor que trabalho, na época tinha link de 2Mbps quando ainda existiam conexões discadas. A interface...

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Palestra no VOL DAY III

Posted by gondim | Posted in FreeBSD | Posted on 22-07-2012

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É com orgulho e motivação que venho estrear essa nova página com uma palestra que ministrei no VOL Day III onde falei sobre HAST (ferramenta nativa do FreeBSD 9 capaz de fazer um cluster e espelhar os dados à nível de blocos entre os discos dos nós), CARP onde nós montamos nosso failover e o ZFS que é o sistema de arquivos mais avançado existente. Juntando os 3 teremos uma solução fabulosa de Alta Disponibilidade.

Palestra em PDF

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Iniciando com o FreeBSD

Posted by admin | Posted in FreeBSD | Posted on 22-07-2012

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Acreditava que seria fácil fazer uma pequena apresentação sobre FreeBSD, mas acredito que muitos que chegaram até aqui ou os que ainda estão por vir, não serão tão “marinheiros de primeira viagem”.

E que nesse início de trabalho possamos contar com a ajuda de todos vocês.

Muito obrigado.

 

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Novo padrão de senha SHA512 no FreeBSD 9.1

Posted by gondim | Posted in FreeBSD, Segurança | Posted on 16-07-2012

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É isso mesmo pessoal, MD5 foi durante muito tempo o padrão de hash para as senhas do sistema. Muitos sistemas ainda usam o MD5 mas agora com a versão 9.1-PRERELEASE e provavelmente a 9.1-RELEASE o padrão passará à ser o SHA512 que é muito mais robusto e seguro que seu antecessor.

Para aqueles que atualizarem o sistema para 9-STABLE, terão essa surpresa ao fazer o mergemaster. Se resolverem usar o padrão novo basta aceitar as modificações no /etc/login.conf e no final gerar o db dele com: cap_mkdb /etc/login.conf

Lembrando que para usar o sistema novo nas senhas, é necessário recriar as senhas usando o passwd. Ex:

# passwd <user>

Estava mais que na hora do MD5 ser aposentado. 😀

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Tuning – uma coisa muito importante e que faz a diferença

Posted by gondim | Posted in Dicas, FreeBSD, Segurança | Posted on 13-07-2012

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Cada Sistema Operacional tem o seu tuning próprio e isso pode realmente fazer a diferença quando você coloca um servidor em produção. Por si só e sem modificações os sistemas tem seus valores padrões de forma que funcionem em qualquer equipamento mas quando necessitamos que o servidor trabalhe com a melhor performance para aquela aplicação, aí sim você começa à quebrar a cabeça.

O problema é que muitos desses parâmetros são obscuros ou tem pouca informação na Internet e quem poderia nos informar mais sobre eles seriam os desenvolvedores que os criaram. No FreeBSD o tuning é feito em 3 lugares:

  • Kernel
  • loader.conf
  • sysctl.conf

O kernel que é instalado é sempre o GENERIC, um kernel suficiente (mínimo) para que o sistema inicie em qualquer hardware para que se tenha uma menor probabilidade de erros com o equipamento. O resultado é um kernel que tem coisas à mais do que necessitamos e ao mesmo tempo faltando outras que precisamos. Um exemplo disso é o firewall que não vem no kernel GENERIC.

Todos os drivers de dispositivos que você não utiliza, deveriam ser removidos do nosso novo kernel mas nunca edite/altere o arquivo GENERIC. Faça uma cópia do GENERIC para outro nome e aí sim edite esse arquivo novo.

Se você instalou um FreeBSD i386 seu kernel GENERIC estará em: /sys/i386/conf/  e se for um amd64 estará em: /sys/amd64/conf/

O NOTES é um cara que possui todas as opções, devices e parâmetros que podemos usar no nosso kernel mas existem 2 NOTES, o NOTES da sua arquitetura e o NOTES genérico que serviria para qualquer arquitetura. Podemos criar um NOTES completo da seguinte forma. Vamos supor que eu esteja em uma arquitetura de 64 bits (amd64):

# cd /sys/amd64/conf
# cat /sys/conf/NOTES NOTES > NOTES-FULL

Agora sim temos um NOTES com todas as opções que podemos usar e servir de referência.

Um exemplo de tuning de Kernel seria o parâmetro HZ que se você tiver um servidor com alto tráfego, um router por exemplo, deveria ser um valor de uns 3000 em máquinas 64 bits SMP.

Então nosso tuning envolve enxugar o kernel e adicionar coisas que usaremos. Abaixo colocarei alguns exemplos de KERNCONF. No final do artigo colocarei o link no qual coletei essas configurações:

=========================================================================

# Just some of them, see also
# cat /sys/{i386,amd64,}/conf/NOTES

# This one useful only on i386
#options         KVA_PAGES=512

# You can play with HZ in environments with high interrupt rate (default is 1000)
# 100 is for my notebook to prolong it’s battery life
#options         HZ=100

# Eliminate datacopy on socket read-write
# To take advantage with zero copy sockets you should have an MTU >= 4k
# This req. is only for receiving data.
# Read more in man zero_copy_sockets
# Also this epic thread on kernel trap:
#    http://kerneltrap.org/node/6506
# Here Linus says that “anybody that does it that way (FreeBSD) is totally incompetent”
#options         ZERO_COPY_SOCKETS

# Support TCP sign. Used for IPSec
options         TCP_SIGNATURE
# There was stackoverflow found in KAME IPSec stack:
# See http://secunia.com/advisories/43995/
# For quick workaround you can use `ipfw add deny proto ipcomp`
options         IPSEC

# This ones can be loaded as modules. They described in loader.conf section
#options         ACCEPT_FILTER_DATA
#options         ACCEPT_FILTER_HTTP

# Adding ipfw, also can be loaded as modules
options         IPFIREWALL
# On 8.1+ you can disable verbose to see blocked packets on ipfw0 interface.
# Also there is no point in compiling verbose into the kernel, because
# now there is net.inet.ip.fw.verbose tunable.
#options         IPFIREWALL_VERBOSE
#options         IPFIREWALL_VERBOSE_LIMIT=10
options         IPFIREWALL_FORWARD
# Adding kernel NAT
options         IPFIREWALL_NAT
options         LIBALIAS
# Traffic shaping
options         DUMMYNET
# Divert, i.e. for userspace NAT
options         IPDIVERT

# This is for OpenBSD’s pf firewall
device          pf
device          pflog
# pf’s QoS – ALTQ
options         ALTQ
options         ALTQ_CBQ        # Class Bases Queuing (CBQ)
options         ALTQ_RED        # Random Early Detection (RED)
options         ALTQ_RIO        # RED In/Out
options         ALTQ_HFSC       # Hierarchical Packet Scheduler (HFSC)
options         ALTQ_PRIQ       # Priority Queuing (PRIQ)
options         ALTQ_NOPCC      # Required for SMP build

# Pretty console
# Manual can be found here http://forums.freebsd.org/showthread.php?t=6134
#options         VESA
#options         SC_PIXEL_MODE

# Disable reboot on Ctrl Alt Del
#options         SC_DISABLE_REBOOT
# Change normal|kernel messages color
options         SC_NORM_ATTR=(FG_GREEN|BG_BLACK)
options         SC_KERNEL_CONS_ATTR=(FG_YELLOW|BG_BLACK)
# More scroll space
options         SC_HISTORY_SIZE=8192

# Adding hardware crypto device
device          crypto
device          cryptodev

# Useful network interfaces
device          vlan
device          tap                     #Virtual Ethernet driver
device          gre                     #IP over IP tunneling
device          if_bridge               #Bridge interface
device          pfsync                  #synchronization interface for PF
device          carp                    #Common Address Redundancy Protocol
device          enc                     #IPsec interface
device          lagg                    #Link aggregation interface
device          stf                     #IPv4-IPv6 port

# Also for my notebook, but may be used with Opteron
device         amdtemp
# Same for Intel processors
device         coretemp

# man 4 cpuctl
device         cpuctl                   # CPU control pseudo-device

# Support for ECMP. More than one route for destination
# Works even with default route so one can use it as LB for two ISP
# For now code is unstable and panics (panic: rtfree 2) on route deletions.
#options         RADIX_MPATH

# Multicast routing
#options         MROUTING
#options         PIM

# Debug & DTrace
options        KDB                     # Kernel debugger related code
options        KDB_TRACE               # Print a stack trace for a panic
options        KDTRACE_FRAME           # amd64-only(?)
options        KDTRACE_HOOKS           # all architectures – enable general DTrace hooks
#options        DDB
#options        DDB_CTF                 # all architectures – kernel ELF linker loads CTF data

# Adaptive spining in lockmgr (8.x+)
# See http://www.mail-archive.com/svn-src-all@freebsd.org/msg10782.html
options         ADAPTIVE_LOCKMGRS

# UTF-8 in console (8.x+)
#options         TEKEN_UTF8

# FreeBSD 8.1+
# Deadlock resolver thread
# For additional information see http://www.mail-archive.com/svn-src-all@freebsd.org/msg18124.html
# (FYI: “resolution” is panic so use with caution)
#options         DEADLKRES

# Increase maximum size of Raw I/O and sendfile(2) readahead
#options MAXPHYS=(1024*1024)
#options MAXBSIZE=(1024*1024)

# For scheduler debug enable following option.
# Debug will be available via `kern.sched.stats` sysctl
# For more information see http://svnweb.freebsd.org/base/head/sys/conf/NOTES?view=markup
#options SCHED_STATS

# A framework for very efficient packet I/O from userspace, capable of
# line rate at 10G (FreeBSD10+)
# See http://svnweb.freebsd.org/base?view=revision&revision=227614
#device netmap

=========================================================================

Agora veremos uns exemplos relacionados ao /boot/loader.conf:

=========================================================================

# Accept filters for data, http and DNS requests
# Useful when your software uses select() instead of kevent/kqueue or when you under DDoS
# Note: DNS accf available on 8.0+
#accf_data_load=”YES”
#accf_http_load=”YES”
#accf_dns_load=”YES”

# Async IO system calls
aio_load=”YES”

# Linux specific devices in /dev
# As for 8.1 it only /dev/full
#lindev_load=”YES”

# Adds NCQ support in FreeBSD
# WARNING! all ad[0-9]+ devices will be renamed to ada[0-9]+
# 8.0+ only
#ahci_load=”YES”
#siis_load=”YES”

# FreeBSD 9+
# New Congestion Control for FreeBSD
# http://caia.swin.edu.au/urp/newtcp/tools/cc_chd-readme-0.1.txt
# http://www.ietf.org/proceedings/78/slides/iccrg-5.pdf
# Initial merge commit message http://www.mail-archive.com/svn-src-all@freebsd.org/msg31410.html
#cc_chd_load=”YES”

# Increase kernel memory size to 3G.
#
# Use ONLY if you have KVA_PAGES in kernel configuration, and you have more than 3G RAM
# Otherwise panic will happen on next reboot!
#
# It’s required for high buffer sizes: kern.ipc.nmbjumbop, kern.ipc.nmbclusters, etc
# Useful on highload stateful firewalls, proxies or ZFS fileservers
# (FreeBSD 7.2+ amd64 users: Check that current value is lower!)
#vm.kmem_size=”3G”

# If your server has lots of swap (>4Gb) you should increase following value
# according to http://lists.freebsd.org/pipermail/freebsd-hackers/2009-October/029616.html
# Otherwise you’ll be getting errors
# “kernel: swap zone exhausted, increase kern.maxswzone”
#kern.maxswzone=”256M”

# Older versions of FreeBSD can’t tune maxfiles on the fly
#kern.maxfiles=”200000″

# Useful for databases
# Sets maximum data size to 1G
# (FreeBSD 7.2+ amd64 users: Check that current value is lower!)
#kern.maxdsiz=”1G”

# Maximum buffer size(vfs.maxbufspace)
# You can check current one via vfs.bufspace
# Should be lowered/upped depending on server’s load-type
# Usually decreased to preserve kmem
# (default is 10% of mem)
#kern.maxbcache=”512M”

# Sendfile buffers
# For i386 only
#kern.ipc.nsfbufs=10240

# FreeBSD 9+
# HPET “legacy route” support. It should allow HPET to work per-CPU
# See http://www.mail-archive.com/svn-src-head@freebsd.org/msg03603.html
#hint.atrtc.0.clock=0
#hint.attimer.0.clock=0
#hint.hpet.0.legacy_route=1

# syncache Hash table tuning
net.inet.tcp.syncache.hashsize=32768
net.inet.tcp.syncache.bucketlimit=32
net.inet.tcp.syncache.cachelimit=1048576

# Increased hostcache
# Later host cache can be viewed via net.inet.tcp.hostcache.list hidden sysctl
# Very useful for it’s RTT RTTVAR
# Must be power of two
net.inet.tcp.hostcache.hashsize=65536
# hashsize * bucketlimit (which is 30 by default)
# It allocates 255Mb (1966080*136) of RAM
net.inet.tcp.hostcache.cachelimit=1966080

# TCP control-block Hash table tuning
net.inet.tcp.tcbhashsize=4096

# Disable ipfw deny all
# Should be uncommented when there is a chance that
# kernel and ipfw binary may be out-of sync on next reboot
#net.inet.ip.fw.default_to_accept=1

#
# SIFTR (Statistical Information For TCP Research) is a kernel module that
# logs a range of statistics on active TCP connections to a log file.
# See prerelease notes http://groups.google.com/group/mailing.freebsd.current/browse_thread/thread/b4c18be6cdce76e4
# and man 4 sitfr
#siftr_load=”YES”

# Enable superpages, for 7.2+ only
# See: http://lists.freebsd.org/pipermail/freebsd-hackers/2009-November/030094.html
vm.pmap.pg_ps_enabled=1

# Usefull if you are using Intel-Gigabit NIC
#hw.em.rxd=4096
#hw.em.txd=4096
#hw.em.rx_process_limit=”-1″
# Also if you have ALOT interrupts on NIC – play with following parameters
# NOTE: You should set them for every NIC
#dev.em.0.rx_int_delay: 250
#dev.em.0.tx_int_delay: 250
#dev.em.0.rx_abs_int_delay: 250
#dev.em.0.tx_abs_int_delay: 250
# There is also multithreaded version of em/igb drivers that can be found here:
# http://people.yandex-team.ru/~wawa/
#
# for additional em monitoring and statistics use
# sysctl dev.em.0.stats=1 ; dmesg
# sysctl dev.em.0.debug=1 ; dmesg
# Also after r209242 (-CURRENT) there is a separate sysctl for each stat variable;
# Same tunings for igb
#hw.igb.rxd=4096
#hw.igb.txd=4096
#hw.igb.rx_process_limit=100

# Some useful netisr tunables. See sysctl net.isr
#net.isr.maxthreads=4
#net.isr.defaultqlimit=10240
#net.isr.maxqlimit=10240
# Bind netisr threads to CPUs
#net.isr.bindthreads=1

#
# FreeBSD 9.x+
# Increase interface send queue length
# See commit message http://svn.freebsd.org/viewvc/base?view=revision&revision=207554
#net.link.ifqmaxlen=1024

# Nicer boot logo =)
loader_logo=”beastie”

=========================================================================

E agora por último mas não tão menos importante um /etc/sysctl.conf:

=========================================================================

# No zero mapping feature
# May break wine
# (There are also reports about broken samba3)
#security.bsd.map_at_zero=0

# If you have really busy webserver with apache13 you may run out of processes
#kern.maxproc=10000
# Same for servers with apache2 / Pound
#kern.threads.max_threads_per_proc=4096

# Max. backlog size
kern.ipc.somaxconn=4096

# Shared memory // 7.2+ can use shared memory > 2Gb
kern.ipc.shmmax=2147483648

# Sockets
kern.ipc.maxsockets=204800

# Mbuf 2k clusters (on amd64 7.2+ 25600 is default)
# Note that defaults for other variables depend on this variable, for example `tcpreass`
# Note for FreeBSD-7 and older: For such high value vm.kmem_size must be increased to 3G
kern.ipc.nmbclusters=262144

# Jumbo pagesize(_SC_PAGESIZE) clusters
# Used as general packet storage for jumbo frames on some network cards
# Can be monitored via `netstat -m`
#kern.ipc.nmbjumbop=262144

# Jumbo 9k/16k clusters
# If you are using them
#kern.ipc.nmbjumbo9=65536
#kern.ipc.nmbjumbo16=32768

# For lower latency you can decrease scheduler’s maximum time slice
# default: stathz/10 (~ 13)
#kern.sched.slice=1

# Increase max command-line length showed in `ps` (e.g for Tomcat/Java)
# Default is PAGE_SIZE / 16 or 256 on x86
# This avoids commands to be presented as [executable] in `ps`
# For more info see: http://www.freebsd.org/cgi/query-pr.cgi?pr=120749
kern.ps_arg_cache_limit=4096

# Every socket is a file, so increase them
kern.maxfiles=204800
kern.maxfilesperproc=200000
kern.maxvnodes=200000

# On some systems HPET is almost 2 times faster than default ACPI-fast
# Useful on systems with lots of clock_gettime / gettimeofday calls
# See http://old.nabble.com/ACPI-fast-default-timecounter,-but-HPET-83–faster-td23248172.html
# After revision 222222 HPET became default: http://svnweb.freebsd.org/base?view=revision&revision=222222
kern.timecounter.hardware=HPET

# Small receive space, only usable on http-server, on file server this
# should be increased to 65535 or even more
#net.inet.tcp.recvspace=8192

# This is useful on Fat-Long-Pipes
#kern.ipc.maxsockbuf=10485760
#net.inet.tcp.recvbuf_max=10485760
#net.inet.tcp.recvbuf_inc=65535

# Small send space is useful for http servers that serve small files
# Autotuned since 7.x
net.inet.tcp.sendspace=16384

# This is useful on Fat-Long-Pipes
#net.inet.tcp.sendbuf_max=10485760
#net.inet.tcp.sendbuf_inc=65535

# Turn off receive autotuning
# You can play with it.
#net.inet.tcp.recvbuf_auto=0
#net.inet.tcp.sendbuf_auto=0

# This should be enabled if you going to use big spaces (>64k)
# Also timestamp field is useful when using syncookies
net.inet.tcp.rfc1323=1
# Turn this off on high-speed, lossless connections (LAN 1Gbit+)
net.inet.tcp.delayed_ack=0

# This feature is useful if you are serving data over modems, Gigabit Ethernet,
# or even high speed WAN links (or any other link with a high bandwidth delay product),
# especially if you are also using window scaling or have configured a large send window.
# Automatically disables on small RTT ( http://www.freebsd.org/cgi/cvsweb.cgi/src/sys/netinet/tcp_subr.c?#rev1.237 )
# This sysctl was removed in 10-CURRENT:
# See: http://www.mail-archive.com/svn-src-head@freebsd.org/msg06178.html
#net.inet.tcp.inflight.enable=0

# TCP slowstart algorithm tunings
# Here we are assuming VERY uncongested network
# Only takes effect if net.inet.tcp.rfc3390 is set to 0
# Otherwise formula teken from http://tools.ietf.org/html/rfc3390
#net.inet.tcp.slowstart_flightsize=10
#net.inet.tcp.local_slowstart_flightsize=100

# Disable randomizing of ports to avoid false RST
# Before usage check SA here www.bsdcan.org/2006/papers/ImprovingTCPIP.pdf
# (it’s also says that port randomization auto-disables at some conn.rates, but I didn’t checked it thou)
#net.inet.ip.portrange.randomized=0

# Increase portrange
# For outgoing connections only. Good for seed-boxes and ftp servers.
net.inet.ip.portrange.first=1024
net.inet.ip.portrange.last=65535

#
# stops route cache degregation during a high-bandwidth flood
# http://www.freebsd.org/doc/en/books/handbook/securing-freebsd.html
#net.inet.ip.rtexpire=2
net.inet.ip.rtminexpire=2
net.inet.ip.rtmaxcache=1024

# Security
net.inet.ip.redirect=0
net.inet.ip.sourceroute=0
net.inet.ip.accept_sourceroute=0
net.inet.icmp.maskrepl=0
net.inet.icmp.log_redirect=0
net.inet.icmp.drop_redirect=1
net.inet.tcp.drop_synfin=1
#
# There is also good example of sysctl.conf with comments:
# http://www.thern.org/projects/sysctl.conf
#
# icmp may NOT rst, helpful for those pesky spoofed
# icmp/udp floods that end up taking up your outgoing
# bandwidth/ifqueue due to all that outgoing RST traffic.
#
#net.inet.tcp.icmp_may_rst=0

# Security
net.inet.udp.blackhole=1
net.inet.tcp.blackhole=2

# IPv6 Security
# For more info see http://www.fosslc.org/drupal/content/security-implications-ipv6
# Disable Node info replies
# To see this vulnerability in action run `ping6 -a sglAac ::1` or `ping6 -w ::1` on unprotected node
net.inet6.icmp6.nodeinfo=0
# Turn on IPv6 privacy extensions
# For more info see proposal http://unix.derkeiler.com/Mailing-Lists/FreeBSD/net/2008-06/msg00103.html
net.inet6.ip6.use_tempaddr=1
net.inet6.ip6.prefer_tempaddr=1
# Disable ICMP redirect
net.inet6.icmp6.rediraccept=0
# Disable acceptation of RA and auto linklocal generation if you don’t use them
#net.inet6.ip6.accept_rtadv=0
#net.inet6.ip6.auto_linklocal=0

# Increases default TTL, sometimes useful
# Default is 64
net.inet.ip.ttl=128

# Lessen max segment life to conserve resources
# ACK waiting time in miliseconds
# (default: 30000. RFC from 1979 recommends 120000)
net.inet.tcp.msl=5000

# Max bumber of timewait sockets
net.inet.tcp.maxtcptw=200000
# Don’t use tw on local connections
# As of 15 Apr 2009. Igor Sysoev says that nolocaltimewait has some buggy realization.
# So disable it or now till get fixed
#net.inet.tcp.nolocaltimewait=1

# FIN_WAIT_2 state fast recycle
net.inet.tcp.fast_finwait2_recycle=1

# Time before tcp keepalive probe is sent
# default is 2 hours (7200000)
#net.inet.tcp.keepidle=60000

# Should be increased until net.inet.ip.intr_queue_drops is zero
net.inet.ip.intr_queue_maxlen=4096

# Protocol decoding in interrupt thread.
# If you have NIC that automatically sets flow_id then it’s better to not use direct_force, and use advantages of multithreaded netisr(9)
# If you have Yandex drives you better off with net.isr.direct_force=1 and net.inet.tcp.read_locking=0 otherwise you may run into some TCP related problems
# If you have old NIC that don’t set flow_ids you may need to patch ip_input to manually set FLOW_ID via nh_m2flow
# FreeBSD 8+
#net.isr.direct=1
#net.isr.direct_force=1
# In FreeBSD 9+ it was renamed to
#net.isr.dispatch=direct

# This is for routers only
#net.inet.ip.forwarding=1
#net.inet.ip.fastforwarding=1

# This speed ups dummynet when channel isn’t saturated
net.inet.ip.dummynet.io_fast=1
# Increase dummynet(4) hash
#net.inet.ip.dummynet.hash_size=2048
#net.inet.ip.dummynet.max_chain_len

# Should be increased when you have A LOT of files on server
# (Increase until vfs.ufs.dirhash_mem becomes lower)
vfs.ufs.dirhash_maxmem=67108864

# Note from commit http://svn.freebsd.org/base/head@211031 :
# For systems with RAID volumes and/or virtualization envirnments, where
# read performance is very important, increasing this sysctl tunable to 32
# or even more will demonstratively yield additional performance benefits.
vfs.read_max=32

# Explicit Congestion Notification (see http://en.wikipedia.org/wiki/Explicit_Congestion_Notification)
net.inet.tcp.ecn.enable=1

# Flowtable – flow caching mechanism
# Useful for routers
#net.inet.flowtable.enable=1
#net.inet.flowtable.nmbflows=65535

# IPFW dynamic rules and timeouts tuning
# Increase dyn_buckets till net.inet.ip.fw.curr_dyn_buckets is lower
net.inet.ip.fw.dyn_buckets=65536
net.inet.ip.fw.dyn_max=65536
net.inet.ip.fw.dyn_ack_lifetime=120
net.inet.ip.fw.dyn_syn_lifetime=10
net.inet.ip.fw.dyn_fin_lifetime=2
net.inet.ip.fw.dyn_short_lifetime=10
# Make packets pass firewall only once when using dummynet
# i.e. packets going thru pipe are passing out from firewall with accept
#net.inet.ip.fw.one_pass=1

# shm_use_phys Wires all shared pages, making them unswappable
# Use this to lessen Virtual Memory Manager’s work when using Shared Mem.
# Useful for databases
#kern.ipc.shm_use_phys=1

# ZFS
# Enable prefetch. Useful for sequential load type i.e fileserver.
# FreeBSD sets vfs.zfs.prefetch_disable to 1 on any i386 systems and
# on any amd64 systems with less than 4GB of avaiable memory
# For additional info check this nabble thread http://old.nabble.com/Samba-read-speed-performance-tuning-td27964534.html
#vfs.zfs.prefetch_disable=0

# On highload servers you may notice following message in dmesg:
# “Approaching the limit on PV entries, consider increasing either the
# vm.pmap.shpgperproc or the vm.pmap.pv_entry_max tunable”
vm.pmap.shpgperproc=2048

=========================================================================

Como podem ver existem muitas variáveis que alteradas de forma correta, podem fazer com que o nosso servidor fique mais seguro, mais rápido, mais estável e principalmente atendendo nossas necessidades. O tuning de um servidor é importante porque nos dá o total controle de como o servidor vai responder às solicitações de carga. Algumas pessoas preferem um sistema mais automático e outras preferem moldar nas suas necessidades. Eu acredito mais em sistemas moldáveis, como é o FreeBSD, pois temos o poder de melhorar onde temos que realmente melhorar.

Existe, logicamente, sempre o lado ruim da questão que é a seguinte: se o sysadmin não souber fazer o tuning correto e o sistema não atender às suas necessidades, este logo culpará o sistema dizendo que não suporta ou não serve para o projeto.

Esse artigo foi feito com dados deste artigo que achei muito interessante e extremamente útil para ser estudado e testado.

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Diretoria nova no core team do FreeBSD

Posted by gondim | Posted in FreeBSD | Posted on 11-07-2012

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De 2 em 2 anos é eleito um novo core team do FreeBSD, vamos dizer que é a diretoria em questão com as maiores responsabilidades dentro do projeto. São responsáveis inclusive por aprovar novos commiters de src do sistema. O core team é eleito pelos próprios desenvolvedores do FreeBSD em votação. A responsabilidade é grande e desejamos um excelente trabalho para eles e que o FreeBSD cresça cada vez mais em qualidade e tecnologia.  🙂

Abaixo o anúncio oficial:

The FreeBSD Project is pleased to announce the completion of the 2012
core team election.  The FreeBSD core team acts as the project’s “board
of directors” and is responsible for approving new src committers,
resolving disputes between developers, appointing sub-committees for
specific purposes (security officer, release engineering, port managers,
webmaster, et cetera), and making any other administrative or policy
decisions as needed.  The core team has been elected by FreeBSD
developers every 2 years since 2000.

Peter Wemm rejoins the core team after a two-year hiatus, with new
members Thomas Abthorpe, Gavin Atkinson, David Chisnall, Attilio Rao and
Martin Wilke joining incumbents John Baldwin, Konstantin Belousov and
Hiroki Sato.

The complete newly elected core team is:
—————————————-
Thomas Abthorpe <tabthorpe@FreeBSD.org>
Gavin Atkinson <gavin@FreeBSD.org>
John Baldwin <jhb@FreeBSD.org>
Konstantin Belousov <kib@FreeBSD.org>
David Chisnall <theraven@FreeBSD.org>
Attilio Rao <attilio@FreeBSD.org>
Hiroki Sato <hrs@FreeBSD.org>
Peter Wemm <peter@FreeBSD.org>
Martin Wilke <miwi@FreeBSD.org>

The new core team would like to thank outgoing members Wilko Bulte,
Brooks Davis, Warner Losh, Pav Lucistnik, Colin Percival and Robert
Watson for their service over the past two (and in some cases, many
more) years.

The core team would also especially like to thank Dag-Erling Smørgrav
for running the election.

Gavin (hat: outgoing core-secretary)

 

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BSDMagazine – mês de julho

Posted by gondim | Posted in FreeBSD, Software Livre, Tecnologia | Posted on 10-07-2012

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Um pouco atrasado mas antes tarde do que nunca! rsrsrs

  • Deploy a full-featured Mail Server on OpenBSD 5.1 with iRedMail
  • freebsd-update as Intrusion Detection System
  • Taming the Blowfish with a Dog
  • Upgrading Ports Using Portmaster
  • Hardening FreeBSD with TrustedBSD and Mandatory Access Controls
  • DNSSEC Part 3: Securing the DNS Hosting Environment
  • Interview with Gabriel Weinberg, Founder of DuckDuckGo
01___okladka
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Fim de linha para as versões 8.1 e 8.2 final do mês

Posted by gondim | Posted in FreeBSD, Segurança, Software Livre | Posted on 01-07-2012

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É pessoal segundo o anúncio abaixo, 31/07 é o fim da linha para o FreeBSD 8.1 e 8.2 no quesito segurança. Aconselha-se para quem tiver usando um desses releases, atualizar para a versão 8.3 pelo menos e continuar tendo suporte em segurança.  🙂

Hello Everyone,

On July 31st 2012, FreeBSD 8.1 and FreeBSD 8.2 will reach their End of
Life and will no longer be supported by the FreeBSD Security Team.
Users of FreeBSD 8.1 and 8.2 are strongly encouraged to upgrade to one
of the newer releases before the that date.

The current supported branches and expected EoL dates are:

  +---------------------------------------------------------------------+
  |  Branch   |  Release   |  Type  |   Release date  |  Estimated EoL  |
  |-----------+------------+--------+-----------------+-----------------|
  |RELENG_7   |n/a         |n/a     |n/a              |February 28, 2013|
  |-----------+------------+--------+-----------------+-----------------|
  |RELENG_7_4 |7.4-RELEASE |Extended|February 24, 2011|February 28, 2013|
  |-----------+------------+--------+-----------------+-----------------|
  |RELENG_8 |n/a |n/a |n/a |last release + 2y|
  |-----------+------------+--------+-----------------+-----------------|
  |RELENG_8_1 |8.1-RELEASE |Extended|July 23, 2010    |July 31, 2012    |
  |-----------+------------+--------+-----------------+-----------------|
  |RELENG_8_2 |8.2-RELEASE |Normal  |February 24, 2011|July 31, 2012    |
  |-----------+------------+--------+-----------------+-----------------|
  |RELENG_8_3 |8.3-RELEASE |Extended|April 18, 2012   |April 30, 2014   |
  |-----------+------------+--------+-----------------+-----------------|
  |RELENG_9 |n/a |n/a |n/a |last release + 2y||-----------+------------+--------+-----------------+-----------------|
  |RELENG_9_0 |9.0-RELEASE |Normal  |January 10, 2012 |January 31, 2013 |
  +---------------------------------------------------------------------+
— Simon L. B. Nielsen FreeBSD Security Officer
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Programação para lançamento do FreeBSD 9.1R

Posted by gondim | Posted in FreeBSD, Software Livre, Tecnologia | Posted on 14-06-2012

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Texto original do anúncio abaixo:

Just a quick note to say we have settled on a target schedule for the
FreeBSD 9.1 Release.  The schedule itself is here:

  http://www.freebsd.org/releases/9.1R/schedule.html

The highlights:

Code Freeze:	July 2nd, 2012
BETA1:		July 6th, 2012
RC1:		July 20th, 2012
RC2:		August 3rd, 2012
Release:	August 13th, 2012

Those are the target dates for when builds start.  The builds becoming
available is usually a few days afterwards (except for the final release
which is often times 4 days to a week after the builds start because
there is more prep work involved...).

Thanks.
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Novas vulnerabilidades – bind 9 e sysret + correção IPv6

Posted by gondim | Posted in Dicas, FreeBSD, Segurança | Posted on 12-06-2012

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Saíram 2 novas vulnerabilidades e um acerto relacionado ao IPv6.

É bom atualizarem os sistemas e sempre se manterem seguros. Abaixo os links com todas as informações necessárias:

http://security.freebsd.org/advisories/FreeBSD-SA-12:04.sysret.asc

http://security.freebsd.org/advisories/FreeBSD-SA-12:03.bind.asc

http://security.freebsd.org/advisories/FreeBSD-EN-12:02.ipv6refcount.asc

O problema do sysret só ocorre em sistemas FreeBSD 64 bits e em  CPU que não seja AMD.

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BSDMagazine – mês de Junho.

Posted by gondim | Posted in FreeBSD, Software Livre, Tecnologia | Posted on 11-06-2012

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BSD Magazine é uma revista mensal de excelente qualidade técnica, visual e gratuita para todo e qualquer profissional que queira ficar bem informado sobre tecnologia e informação utilizando BSD e outros Softwares Livres.

A revista encontra-se em idioma Inglês e para baixá-la basta informar o seu e-mail e clicar para baixar. Todas as outras edições anteriores também podem ser baixadas. Seu formato está em pdf.

Conteúdo:

– DNSSEC: Threats to DNS Transactions Part 2

– Anatomy of a FreeBSD Compromise Part 6

– Using Qjail to set up the basejail

– PostgreSQL: Server-Side Programming Part 2

– Synchronization Problems or: How I Learned to Stop Worrying and Love the Sleep Mutex

– ZFS Madness with BEADM – How To

Bsd_06_2012

 

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