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[sevenlayermuddle]

Without wishing to incur the wrath of the forum's penguin colony, just though I'd mention...

As part of my overnight backup strategy, just in case Google ever let me down and lose all my mail, my clever Fedora server connects to gmail and uses an IMAP 'getmail' script to append all new messages on the server to a local archive.   But for the past couple of days it had been failing, the google server resetting the connection during download on one troublesome mailbox.     

Today I got around to investigating.   Seems it began a couple of days ago when recent talk of malware began to prey on my conscience so, for the first time in nearly a year, I performed an update.

Still not sure exactly what went wrong, but it looks like the update has caused my 'getmail' to forget all the messages that are already downloaded, so it is trying to download all messages since the dawn of time, whereas google have (massive, but finite) daily bandwidth limits.  Good job I investigated, as Google warn they may suspend access in such circumstances.

I have already figured out a solution, and all should be well again soon.   But as 'tis often said, whilst system updates may protect you from nasties, there is no telling whether the updates will be nastier than the nasties

[burakkucat]

. . . Fedora server . . .

[<cough> Fur ball, excuse me.]

The words "Fedora" and "server" should never be used in the same sentence. Fedora is a "software hacker's playground" with a six monthly churn and no stability. It should never be used for a server, otherwise issues such as the above are bound to occur.

If you like an RPM package based system, 7LM, please consider RHEL. If the support license is too expensive, then I would recommend that you look at either CentOS or Scientific Linux, clone systems built from exactly the same source code as RHEL.

I am making this post from my Dell Latitude E5500 laptop system, upon which I have the server version of RHEL 6u4 installed! (That may seem a bit odd but I have a reason . . . my connection with the ELRepo Project.)

[Duo2 ~]$ rpm -qa redhat-release\*
redhat-release-server-6Server-6.4.0.4.el6.x86_64
[Duo2 ~]$ uname -a
Linux Duo2 3.12.0-1.el6.elrepo.x86_64 #1 SMP Mon Nov 4 15:14:03 EST 2013 x86_64 x86_64 x86_64 GNU/Linux
[Duo2 ~]$

[sevenlayermuddle]

Wise words, and taken on board.   

I forget exactly why I chose Fedora, I think it goes back to a time when better half was at that time (in day job) working with redhat, hence I had free and reliable 'support'.   But I do appreciate RHEL is different fish in a different kettle.

My big upheaval tends to come when I want to migrate to a newer version of mythtv (the main job of my 'server'), when I take the opportunity to migrate to the latest Fedora too.   Perhaps once every 18 months.   Next time around, I shall give serious thought to moving on, and will look at these suggested alternatives.

That said... I strongly suspect my specific issue would have been caused simply by an update to 'getmail'.   Is it really that likely that the 'new' version of getmail would behave any differently on a different linux?

[burakkucat]

RHEL and (thus) the clone systems, Scientific Linux and CentOS, are built for long term stability -- explicitly for servers.

Persons who make use of any of those distributions for a MythTV server may find that they need to use the kernel-lt package, available from the ELRepo Project. A certain burakkucat and his associate, toracat, ensure that those kernel packages are built purrfectly. 

As for your problem with "getmail", I am not sure. RHEL does not have such an utility . . . 

[sevenlayermuddle]

[

As for your problem with "getmail", I am not sure. RHEL does not have such an utility . . . 

To be fair, getmail is an indepentently written utility, which I find rather useful.

http://pyropus.ca/software/getmail/

It is available as rpm for fedora and, I thought, for RHEL too?

Since it is installed in rpm format, it is my understanding that it will get 'updated' automatically, whenever I permit updates to occur.   I apologise if I am mistaken in that.   But if correct, and if I were to use RPM getmail on RHEL, would the same problem (unwelcome updates) not arise?

I hasten to add I have not absolutely confirmed beyond doubt hat it was an unwelcome update to getmail that caused my problems, nevertheless it is a useful hypothetical example.

[roseway]

Since it is installed in rpm format, it is my understanding that it will get 'updated' automatically, whenever I permit updates to occur.   I apologise if I am mistaken in that.   But if correct, and if I were to use RPM getmail on RHEL, would the same problem (unwelcome updates) not arise?

A small misunderstanding here, I suspect. If you've manually installed a third party package (getmail in this case) it won't get upgraded automatically when you do a system upgrade. In fact, it's generally frowned upon to install third party software this way; the 'correct' way is to build the software from source using the specific tools available for your distro. In Debian, which I use, there's an installation package called checkinstall which does this job, and I'm sure that it's also available in RH.

[sevenlayermuddle]

Since it is installed in rpm format, it is my understanding that it will get 'updated' automatically, whenever I permit updates to occur.   I apologise if I am mistaken in that.   But if correct, and if I were to use RPM getmail on RHEL, would the same problem (unwelcome updates) not arise?

A small misunderstanding here, I suspect. If you've manually installed a third party package (getmail in this case) it won't get upgraded automatically when you do a system upgrade. In fact, it's generally frowned upon to install third party software this way; the 'correct' way is to build the software from source using the specific tools available for your distro. In Debian, which I use, there's an installation package called checkinstall which does this job, and I'm sure that it's also available in RH.

I simply typed (as root) 'yum update -y', then went out for a beer.   I could have skipped the -y, but that would have meant sitting in front of the system answering occasional and interminable prompts during valuable drinking time.

I was under the impression that 'yum update' was the recommended update vehicle for rpm based distributions, and that it attempted updates to all rpm-installed packages including manually installed (by yum/rpm)?

http://www.centos.org/docs/5/html/yum/sn-updating-your-system.html

Genuinely interested in learning from this one so I can avoid mistakes in future.

[tickmike]

@ roseway +1.

On PCLinuxOS it has 'getmail' in 'synaptic' package manager and says...

"POP3 mail retriever with reliable Maildir delivery
getmail is intended as a simple replacement for fetchmail for those people
who do not need its various and sundry configuration options, complexities,
and bugs.  It retrieves mail from one or more POP3 servers for one or more
email accounts, and reliably delivers into a Maildir specified on a
per-account basis.  It can also deliver into mbox files, although this
should not be attempted over NFS.  getmail is written entirely in python."

It's used for POP3 not IMAP   

[burakkucat]

I simply typed (as root) 'yum update -y', then went out for a beer.   I could have skipped the -y, but that would have meant sitting in front of the system answering occasional and interminable prompts during valuable drinking time.

Usage of the -y flag is a bad choice. You would only be prompted once, after the package list for the transaction had been displayed. It is always recommended to review the intended transaction and then, if satisfactory respond with a y or otherwise . . .

I was under the impression that 'yum update' was the recommended update vehicle for rpm based distributions, and that it attempted updates to all rpm-installed packages including manually installed (by yum/rpm)?

The yellow dog updater, modified, will only update packages from enabled repositories or install / update / delete a named package, to which it has access.

http://www.centos.org/docs/5/html/yum/sn-updating-your-system.html

Genuinely interested in learning from this one so I can avoid mistakes in future.

Please don't use of out-of-date CentOS documentation. I would recommend consulting the current versions, which are available from Red Hat.

[sevenlayermuddle]

mbox
It's used for POP3 not IMAP   

Sorry Mike, I reallise you are just quoting from PCLinuxOS, but that is categorically incorrect.  Getmail has many IMAP features works beatifully with IMAP, it has performed faultlessly for a year now, and continues to do so apart from this one-off update glitch.

I chose to use it because I could find nothing better.   

As linked earlier...

http://pyropus.ca/software/

... many references to IMAP and full instructions.

@Mr Cat, sorry I linked to out of date docs.   It is simply the page that came up tops in a google search for 'yum update'.

[burakkucat]

@Mr Cat, sorry I linked to out of date docs.   It is simply the page that came up tops in a google search for 'yum update'.

Here is a link to the relevant chapter in the latest RHEL 6 documentation, especially for you. 

[sevenlayermuddle]

@Mr Cat, sorry I linked to out of date docs.   It is simply the page that came up tops in a google search for 'yum update'.

Here is a link to the relevant chapter in the latest RHEL 6 documentation, especially for you. 

For which I thank you, although I am not sure it will shed any new light.

Regarding '-y', as stated earlier, I regard it as impractical to sit at the console vetting/approving each individual RPM.  Even just for mythtv, I believe there were quite a number of updates, to obscurely named packages. 

It has also been my experience with the open source comunity  (not just linux) that compatibility between versions of components is not regarded as essential, hence selective upgrades is highly likely to lead to problems.

 

[burakkucat]

. . .  vetting/approving each individual RPM.

No, that is not how yum operates. It will analyse the entire transaction, display what it intends to do and then ask, just once, "Yes/No".

[sevenlayermuddle]

. . .  vetting/approving each individual RPM.

No, that is not how yum operates. It will analyse the entire transaction, display what it intends to do and then ask, just once, "Yes/No".

I could have sworn it prompted me many times without the '-y' but I accept I may be wrong.

But does this have any bearing on the scenario that I described, i.e. would absence of '-y' have changed anything?

To recap…

* It had been a long time since I applied updates.
* Conscience got the better of me, so I allowed the updates to proceed.
* As a result of the updates, something broke, just as I might expect from windows system updates.
* Being reminded of the fragility of updates on a windows system, I commented 'Linux no better than windows', though I concede that in many respects it is a lot better.

Nothing that has been said alters any of above, or changes my opinion.  I will be a lot more wary before updating the server again, and have lost a lot of trust in the yum/rpm update mechanism.   

Clearly there would have been ways in which I could have updated other components without updating getmail, but I had no reason to expect it to break anything, so why would I have wanted to exclude it?   Heck, I still don't even know if it was a getmail update that did the damage, or just a side-effect of some other update.   The only reason for updating was to 'clear my conscience' as it had been a long time since the last update, so I just chose a moment when mythtv had no imminent recordings and updated the lot.  What's to criticise?

I clearly ought to apologise however for any ruffled feathers…     I'd also point out that I posted in 'chit-chat', meaning not to be taken too seriously.   

I hope the penguins are not just a little bit over-sensitive to criticism?   

[sevenlayermuddle]

PS:  As I sip my cocoa, I hear two of the discs in the server spinning up.  That suggests my backup script is running, and (if my getmail script fix works) I will awake to a pleasant email from the server, usually about 4am, saying 'Backup Completed OK'.

Time will tell