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39

You can edit tomcat/conf/server.xml's HTTP/1.1 Connector entry, and add a maxHttpHeaderSize="65536" to increase from the default maximum of 8K or so, to 64K. I imagine that you could up this number as high as necessary, but 64K suffices for my needs at the moment so I haven't tried it. <Connector port="8080" maxHttpHeaderSize="65536" protocol="HTTP/1.1" ...


36

The client does not know in advance that the response will be too large, so it will query the server via UDP. The server will respond via UDP and will include as much as possible and set the truncated header bit ("TC" http://www.networksorcery.com/enp/protocol/dns.htm). The client can then resend the request via TCP and get the full response. See also: ...


23

This is a common error. You cannot use a CNAME RR for your root domain (e.g. company.com) and define additional resource records for the same zone. See Why can't I create a CNAME record for the root record? and RFC1034 section 3.6.2 for details: If a CNAME RR is present at a node, no other data should be present; this ensures that the data for a ...


17

It would definitely create a problem if you were to point your MX records at CNAME records since it is against the standards. The clearest explanation is provided by RFC2181 §10.3: 10.3. MX and NS records The domain name used as the value of a NS resource record, or part of the value of a MX resource record must not be an alias. Not only is ...


15

It is generally considered a good practice to serve localhost, 0.0.127.in-addr.arpa and the RFC-1918 reverse zones on your internal DNS system to prevent sending queries from them out to the internet. It saves time (you get replies for those queries quickly), bandwidth (no requests leaving your network for zones that shouldn't exist), and relieves the load ...


15

Not just RFC 1918...also RFC 6598, i.e. 100.64.0.0/10 CGN space. Both of those are private networks, but the latter is more recently standardized and less known. This isn't unusual from a traceroute standpoint. You aren't actually talking to those 10space and 100space hosts directly, you're sending packets with incrementally larger TTLs to your next hop ...


12

You are probably looking for RFC 6056 - Recommendations for Transport-Protocol Port Randomization ("Best Current Practice"). Technically there is no requirement that the ephemeral port be >1024 or random (you could build a system that always initiates connections from port 12 because you like the number 12), it's just not "normal" to do so (and an awful ...


12

Yes, 127.0.0.1 is called loopback network and is always available. This address points to the machine itself. EDIT: To answer the second part of the question: Yes, machines A and B can be on the same network (but NOT the same as 127.0.0.1, while loopback is virtual) if the netmask is set properly. Use IP calculator to get what you need.


11

RFC 822 actually gives an example of this usage. It required (Section 4.4) that the Sender: header be present when it was used. A.2.7. Agent for member of a committee George's secretary sends out a message which was authored jointly by all the members of a committee. Note that the name of the committee cannot be ...


10

@yoonix has sent a link that might have a solution. Link-local, also known as APIPA. 169.254.0.0/16 - This is the "link local" block. As described in RFC3927, it is allocated for communication between hosts on a single link. Hosts obtain these addresses by auto-configuration, such as when a DHCP server cannot be found. If I were your customer, I'd ...


9

Don't do accept-and-bounce, do as much filtering/rejecting at connection time as possible. This helps to prevent Backscatter Emails and Joe Jobs, and keeps unwanted email out of your mail system.


9

It is permissible for routers to connect to each other using RFC1918 or other private addresses, and in fact this is very common for things like point-to-point links, and any routing that takes place inside an AS. Only the border gateways on a network actually need publicly routeable IP addresses for routing to work. If a router's interface doesn't connect ...


9

It's definitely compliant. The whole point of Quoted-Printable, and the rest of the MIME series of RFCs (RFC 2045 through RFC 2049), is to allow the encoding of data that otherwise would not be valid in e-mail. RFC 2822 explicitly (and repeatedly!) points readers at those RFCs for information on how to do this.


9

You'd think they are valid because the root name-servers are all single-letter hosts (a.root-servers.net), and the DNS spec doesn't create a specific exception for them. The RFC in question is specifically for host-file format, not DNS. DNS was defined in a later RFC (RFC 1035 starts it). RFC 1123 (1989) states it clearly. The syntax of a legal Internet ...


8

Yes you are correct. The section you quoted says that it must be a quoted string OR a dot atom. Since its clearly not a quoted string (the lack of enclosing " makes that clear) it must be a dot-atom... That leads us to the definition of dot-atom: Look at this except from RFC 5322 (3.2.3 - page 13) (RFC 2822 contains a similar section) the hint is the 1* ...


7

No. Spammers do not care about whether you want their spam or not.


7

Better in what way specifically? RFC 2790 obsoleted RFC 1514.


6

I'd go as far as saying that there is no connection, at all, between the records in DNS and what a server tells you its name is, so from a DNS point of view, the only difference between your two scenarios is what name goes where. From the machine's point of view, it doesn't care. However, from your users' perspective, I'd pick one of the two and then stick ...


6

Automated processing is a big reason. You want to be able to send any bounces/autoreplies/errors to be processed separately, otherwise those messages disappear, or get ignored, or some poor sap has to dig through them. Yes, adding an X- header for processing is possible, but a lot of the time bounces/etc. won't include the original email or only a mangled ...


6

In your case, the same string you're using minus the ptr should do the trick. v=spf1 a mx ~all


6

The preferred option is to bounce immediately at the Internet gateway. This results in a failure for the server (most likely a spambot) that you are rejecting. However, it is simpler to use this to check for the existence of an email address. Accept and bounce is simpler for the Internet gateway, but generates back scatter spam. In effect, you make your ...


5

From Wikipedia: Assigned as "TEST-NET-3" in RFC 5737 for use solely in documentation and example source code and should not be used publicly. - This tells me that you should not use TEST-NET-3. One thing you appear to be overlooking: How do you suppose that you'll be able to communicate with the device or that the device will be able to communicate with ...


5

The first three digits "550" are the code that is necessary for the SMTP protocol. This is used during SMTP dialog to handle errors, success or failures. The dotted version is the so called extended return code. In this code you can specify a more detailed response for humans or automated scripts. But they are not necessary for an SMTP server to work. But ...


5

E-mail without MIME support (which is optional) is defined by RFC 5322, and only allows "printable" ASCII characters. MIME extends this standard and allows other encoding schemes for certain fields (subject included). When encoding a header, you use the "Encoded-Word" method: The form is: "=?charset?encoding?encoded text?=". charset may be any ...


5

Make it configurable. Should I buy IPv4 addresses? Yeah. TRY THAT. First, you do not buy them, you "lease" them by membership. Second this requires an AS and 2 uplinks. Third, this requires a reason and "we do not want to suppose a proper network infrasctructure" is a reason resulting in laughter (and a rejection), not you getting IP addresses ...


5

The mail from: in the smtp conversation is designed to be the place where bounces will go The From: header in the message body is used to display to the recipient and as the reply address if the Reply-to: header isn't set. Emails which shouldn't generate a bounce should set the empty sender in the envelope, for instance a return receipt will usually have: ...


5

yes of course, 127.0.0.1 is always available. It is the "localhost", pointing to the machine itself without going to a real net. It is the address of the loopback device and it is present even if no net card is installed (on every modern OS at least). 192.168.x.x is a set of 256 C classes for internal use (see RFC1918) so you can have 65k hosts (as if it ...


5

The length of an HTTP GET request is not enforced by RFC2616, as Microsoft reports for its IE max length support page. So, the maximum GET length is a client (browser) related issue. If your app is used by people you can force to use a given browser then you can simply find what is the length this browser support. In every case I suggest a look to the ...


5

Nat firewalls translate your external ip address to your internal ip address. Have a look at the accepted answer on this now famous question about subnetting, which should answer your questions. Private IPs, in the ranges that you show in your question, are not publicly routable so need an external address to make it out onto the internet, hence NAT


5

Normally, a router would never receive a packet with a hop limit of zero, but it may happen at some point due to sloppy coding or malicious computers or network degradation. The issue is what happens when you decrement something that is zero. If it's unsigned, then it wraps around and lasts another 65535 hops.



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