5 ms·

I dont think this is a good idea -- if ec2 goes down (as it has in the past) you risk losing email

by niggler 14y ago

rabidsnail 14y ago
I risk new messages getting bounced, but all of my email is backed up on my computer. And I'd archive everything to s3 (which has never lost data to my knowledge) in case both my ec2 instance and my laptop disappeared.
notatoad 14y ago
SMTP doesn't just drop messages if the destination server is unavailable. It'll either get held back at an intermediary server until your server comes up again, or else it will be bounced back to the sender.
- ams6110 14y ago
  SMTP does sometimes just drop messages, it's not a protocol that guarantees delivery
  - ars 14y ago
    That's not true. It should either send the email to the recipient or return it to sender. But it should never just drop the message (except for bounces which can be dropped since there is nowhere to send them if delivery fails).
    - danielweber 14y ago
      I think you and the parent are using different meanings of "guarantee." Yes, everything in the protocol leads to the fact that nothing should drop an email unless it has passed responsibility of it to another server which has accepted the message. In practice, lots of times things don't work.
      - ams6110 14y ago
        Yes, one misconfigured server between source and destination can "eat" email and you'll never be the wiser. Doesn't happen often, but it can and the protocol does not detect it.
  - overbroad 14y ago
    An SMTP daemon will try to send the message a certain number of times, at a certain interval, then, eventually, it will stop ("bounce"). You can configure these settings if you run your own SMTP service.
jrockway 14y ago
There's a reason why a domain can have multiple mail exchanger records.
icebraining 14y ago
You can set up a different mail server with a lower priority. I run my own server on a VPS, but have Google Apps' SMTP server as backup for those cases, and it's been working fine for months.
- overbroad 14y ago
  Assuming your ISP is not blocking port 25 and your internet address is not on some blacklist you can send mail directly from your machine. No need to use intermediary SMTP servers. Is it possible that someone people might like to use their native SMTP capability for low volume noncommercial email? Does every person who sends email have some overwhelming urge to send spam? Such that we must place pseudo control over sending email, any email whether commercial or noncommercial, in the hands of "email providers"? Good on you for running your own service.
  - icebraining 14y ago
    My ISP doesn't block port 25, but since my IP address is technically dynamic, it's on Spamhaus' Policy Black List. That said, my ISP offers SMTP servers for proxying outgoing messages, so I used that for a while. I switched to a VPS because my home server died.
    - overbroad 14y ago
      Gotta love that Spamhaus logic. Spammers use cheap dynamic IP's therefore anyone with a cheap dynamic IP that sends an email is a spammer. Is it cheaper for you to get a static IP from a VPS than from your ISP?
      - DanBC 14y ago
        "Spammers use cheap dynamic IP's therefore anyone with a cheap dynamic IP that sends an email is a spammer." That's not what they're saying. "Very many spam emails come from people running an email server on a dynamic IP. Some companies were happy to host spam sending companies, and would put them in dynamic ranges so they could continue to get money from those spam sending companies and keep changing the IP address. The ratio of good email servers to bad email servers on dynamic IPs is so poor that blocking all dynamic IPs is, unfortunately, the only reasonably solution". You can be on a dynamic IP and send email. Just don't send that email from a server on a dynamic IP.

I dont think this is a good idea -- if ec2 goes down (as it has in the past) you risk losing email

by niggler 14y ago

I dont think this is a good idea -- if ec2 goes down (as it has in the past) you risk losing email

I risk new messages getting bounced, but all of my email is backed up on my computer. And I'd archive everything to s3 (which has never lost data to my knowledge) in case both my ec2 instance and my laptop disappeared.

notatoad 14y ago

SMTP doesn't just drop messages if the destination server is unavailable. It'll either get held back at an intermediary server until your server comes up again, or else it will be bounced back to the sender.

ams6110 14y ago
SMTP does sometimes just drop messages, it's not a protocol that guarantees delivery
- ars 14y ago
  That's not true. It should either send the email to the recipient or return it to sender. But it should never just drop the message (except for bounces which can be dropped since there is nowhere to send them if delivery fails).
  - danielweber 14y ago
    I think you and the parent are using different meanings of "guarantee." Yes, everything in the protocol leads to the fact that nothing should drop an email unless it has passed responsibility of it to another server which has accepted the message. In practice, lots of times things don't work.
    - ams6110 14y ago
      Yes, one misconfigured server between source and destination can "eat" email and you'll never be the wiser. Doesn't happen often, but it can and the protocol does not detect it.
- overbroad 14y ago
  An SMTP daemon will try to send the message a certain number of times, at a certain interval, then, eventually, it will stop ("bounce"). You can configure these settings if you run your own SMTP service.

jrockway 14y ago

There's a reason why a domain can have multiple mail exchanger records.

icebraining 14y ago

You can set up a different mail server with a lower priority. I run my own server on a VPS, but have Google Apps' SMTP server as backup for those cases, and it's been working fine for months.

overbroad 14y ago
Assuming your ISP is not blocking port 25 and your internet address is not on some blacklist you can send mail directly from your machine. No need to use intermediary SMTP servers. Is it possible that someone people might like to use their native SMTP capability for low volume noncommercial email? Does every person who sends email have some overwhelming urge to send spam? Such that we must place pseudo control over sending email, any email whether commercial or noncommercial, in the hands of "email providers"? Good on you for running your own service.
- icebraining 14y ago
  My ISP doesn't block port 25, but since my IP address is technically dynamic, it's on Spamhaus' Policy Black List. That said, my ISP offers SMTP servers for proxying outgoing messages, so I used that for a while. I switched to a VPS because my home server died.
  - overbroad 14y ago
    Gotta love that Spamhaus logic. Spammers use cheap dynamic IP's therefore anyone with a cheap dynamic IP that sends an email is a spammer. Is it cheaper for you to get a static IP from a VPS than from your ISP?
    - DanBC 14y ago
      "Spammers use cheap dynamic IP's therefore anyone with a cheap dynamic IP that sends an email is a spammer." That's not what they're saying. "Very many spam emails come from people running an email server on a dynamic IP. Some companies were happy to host spam sending companies, and would put them in dynamic ranges so they could continue to get money from those spam sending companies and keep changing the IP address. The ratio of good email servers to bad email servers on dynamic IPs is so poor that blocking all dynamic IPs is, unfortunately, the only reasonably solution". You can be on a dynamic IP and send email. Just don't send that email from a server on a dynamic IP.