Exchange - insufficient system resources (boa explicação)

http://woshub.com/exchange-error-452-4-3-1-insufficient-system-resources/

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Celular - o que é 4.5G ou 4G+

http://www.telesintese.com.br/claro-investe-no-45g-que-tera-9-mil-sites-ate-dezembro/

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IPv6 - Configurando 6to4 no MikroTik para uma rede inválida

O ambiente de teste utiliza-do foi com um modem Velox roteado, um Router Board MikroTik RB433, um notebook e o Tunnel Broker (Hurricane Electric).

Configurações de IPs

 - Modem: 192.168.1.1

 - Mikrotik: 192.168.1.254

Primeiramente precisamos configurar o IP do Mikrotik na zona DMZ (Zona Desmilitarizada) do modem roteado. Assim todas as conexões ao ip válido do modem serão redirecionadas para o mikrotik.

Em seguida loga-se no site Tunnel Broker (tunnelbroker.net) para poder criar o túnel 6to4.

Clique no menu esquerdo em "Create Regular Tunnel" e cadastre o ip válido do modem (www.meuip.com.br)

Pronto, a configuração no lado servidor do túnel 6to4 esta criado. Agora falta o lado cliente.

Clique em "Example Configurations" e selecione "Mikrotik"

Ex.:

/interface 6to4 add comment="Hurricane Electric IPv6 Tunnel Broker" disabled=no local-address=201.58.125.113 mtu=1280 name=sit1 remote-address=209.51.161.58

/ipv6 route add comment="" disabled=no distance=1 dst-address=2000::/3 gateway=2001:470:4:818::1 scope=30 target-scope=10

/ipv6 address add address=2001:470:4:818::2/64 advertise=yes disabled=no eui-64=no interface=sit1

Agora abra o "winbox" e conecte no Mikrotik. Certifique-se que os pacotes IPv6 estão ativados indo no menu "System" -> "Packages".

Vá em "New Terminal" e execute as três linhas oferecidas pelo site Tunnel Broker.

Para fechar o túnel atrás de um NAT deve-se alterar o IP local do túnel. Para isso no menu "Interfaces" e edite o túnel "sit1", trocando o ip "Local Address" para o ip do mikrotik (192.168.1.254).

Para testar se o túnel foi fechado, localise o ip do Server IPv6 no site tunnel broker e tente fazer o ping através do mikrotik

Ex.: Server IPv6 Address: 2001:470:4:818::1/64

No mikrotik vá em "Tools" -> "Ping", preencha o ip e start. O status retornado deve ser "echo reply".

Verifique no site do Tunnel Broker qual é a sua Rede.

Ex.: Routed /64: 2001:470:5:818::/64

No mikrotik vá em "IPv6" -> "Addresses" e cadastre um ip, dentro da rede recebida, para o seu mikrotik na interface onde estarão os clientes.

Ex. 2001:470:5:818::1/64

No computador cliente verifique se o IPv6 foi configurado automaticamente. Caso não seja configurado automaticamente configure com o ip e gateway dentro da rede recebida.

Ex.:

 IP: 2001:470:5:818::2

 Mascara: 64

 Gateway: 2001:470:5:818::1

No site Tunnel Broker verifique os ips de DNS para serem colocados nos clientes e configure os dns dos clientes.

Ex.:

Anycasted IPv6 Caching Nameserver: 2001:470:20::2

Anycasted IPv4 Caching Nameserver: 74.82.42.42

Agora abra a console no cliente e tente pingar o endereço:

> ping6 ipv6.google.com

Acesse o site http://www.ipv6.br/ , verifique no topo da página se o IPv6 aparece e se o globo no lado direito da tela esta girando.

Referências:

• http://www.bitabit.eng.br/2011/02/03/conectividade-ipv6-em-casa-%E2%80%93-parte-1/
• http://tunnelbroker.net/
• https://sites.google.com/site/silviogarbes/sistemas/redes/mikrotik/ipv6---configurando-6to4-no-mikrotik-para-uma-rede-invalida

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Disabling Mikrotik Hotspot DNS Proxying for Authenticated Users

My wireless ISP (WISP) uses the Mikrotik hotspot feature with RADIUS on the back end to authenticate our users. This implements a captive portal that redirects all DNS requests so that the user is taken to a login page if they’re not logged in. Once they log in once, the system associates their radio with their account, and they don’t have to log in anymore under normal circumstances.
However, once logged in, users still have all their DNS requests proxied through the routers. A lot of users want to use their own DNS (like OpenDNS or Google Public DNS), and that’s fine with me, but a user ran the namebench utility and found that their DNS was being forcibly proxied.
It took some hunting, but I finally found this post on the Mikrotik forums which details how to get around this. Basically:

• The hotspot adds dynamic DNS redirect rules. If you go to /ip firewall nat and just print, these rules don’t show up. If you do print dynmic they do. The relevant lines are:
  
2 D chain=hotspot action=redirect to-ports=64872 protocol=udp dst-port=53 log=no log-prefix=""
3 D chain=hotspot action=redirect to-ports=64872 protocol=tcp dst-port=53 log=no log-prefix=""

• We still want non-logged-in-users to have their DNS redirected, so we need to add something here that will enable authenticated hotspot users through. The magic incantation here (because it’s entries 2 and 3) is set 2,3 hotspot=!auth, which results in the following:
  
2 D chain=hotspot action=redirect to-ports=64872 protocol=udp hotspot=!auth dst-port=53 log=no log-prefix=""
3 D chain=hotspot action=redirect to-ports=64872 protocol=tcp hotspot=!auth dst-port=53 log=no log-prefix=""


And now namebench works as expected.

This entry was posted in Networking, RouterOS, Tech on 2015-01-09 by Brock Tice.

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Sites - A falta de refrigeração dá nisto!

http://www.fr.net.br

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