Rytis's questions

Google Search Console is showing the infamous "Couldn't fetch" status for my sitemap. In my case however it is not a hidden "Pending" status, but rather a true failure to fetch. For example, my last attempt to submit was 20 days ago - it still shows as Couldn't fetch.

Inspecting server logs shows that the sitemap wasn't even attempted to be fetched in that period of time.

Loading the sitemap file through the Inspect URL feature retrieves the contents, so the server side of things seems to be fine. Looks like an issue on the Google side, but I cannot think of any way to push through to get the file fetched.

I tried changing the filenames, submitting a more basic sitemap (doesn't show up on the server side logs either), checking robots.txt - nothing seems to help.

I am trying to route requests to different backends based on the existence of an URL param. I tried the following, but it never matches, even if my request contains a host param, e.g. POST http://127.0.0.1/result?build=2021041601&host=foo123:

acl has_host_urlparam urlp(host)
use_backend backend-host if has_host_urlparam
default_backend backend-generic

Do I have to compare the value returned from urlp() with something to check for existence of the param?

I had a 95% CPU usage with a single haproxy process, so I switched to nbproc 2.

I have a two frontends and two backends; I pinned 1 frontend and 1 backend to process 1, and pinned the remaining two to process 2. I expected the load on the CPU cores to be distributed based on the load of the frontend/backend groups, however, now I have two haproxy processes, one using 20% CPU, the other still using 95% CPU. Why is that the case?

I am not yet dropping connections, but I will be as I start using even more CPU on that one thread.

Configuration is as follows:

global
    nbproc 2
    maxconn 150000
    user root # haproxy
    group root # haproxy
    daemon
    stats socket /var/run/haproxy.sock group haproxy mode 775

defaults
    mode tcp
    timeout connect 5000ms
    timeout client 130s
    timeout server 130s

frontend http-in
    bind-process 2
    bind *:80
    mode http
    maxconn 40000

    acl host_typea hdr(host) -i typea.example.com
    acl host_typeb hdr(host) -i www.example.com

    use_backend typea-backend if host_typea
    use_backend typeb-backend if host_typeb

    default_backend typeb-backend

frontend proxy-customers-frontend
    bind-process 1
    bind *:20000
    maxconn 10000
    option httpclose
    mode http
    log global
    acl host_typec hdr(proxy-authorization) -m len gt 80
    use_backend typec-backend if host_typec

    default_backend typed-backend

backend typea-backend
    bind-process 2
    mode http
    balance url_param ip check_post

    server localhost-30000 127.0.0.1:30000 check
    server localhost-30001 127.0.0.1:30001 check
    server localhost-30002 127.0.0.1:30002 check
    server localhost-30003 127.0.0.1:30003 check
    server localhost-30004 127.0.0.1:30004 check
    server localhost-30005 127.0.0.1:30005 check
    server localhost-30006 127.0.0.1:30006 check
    server localhost-30007 127.0.0.1:30007 check

backend typeb-backend
    bind-process 2
    mode http
    option forwardfor
    server localhost-81 127.0.0.1:81 check

backend typec-backend
    bind-process 1
    mode http
    server localhost-19999 127.0.0.1:19999 check

backend typed-backend
    bind-process 1
    mode http

    server localhost-20001 127.0.0.1:20001 check
    server localhost-20002 127.0.0.1:20002 check
    server localhost-20003 127.0.0.1:20003 check
    server localhost-20004 127.0.0.1:20004 check
    server localhost-20005 127.0.0.1:20005 check
    server localhost-20006 127.0.0.1:20006 check
    server localhost-20007 127.0.0.1:20007 check
    server localhost-20008 127.0.0.1:20008 check

I have a haproxy server which gets limited to some 60k connections. I think it is because of ephemeral port limit as I have 1:1 connection mapping, so all my outgoing connections go to the same server.

Here is what I think could help me: I can add a new network interface (eth1) with a new IP. I would then add a duplicate backend server definition and I believe the new destination will get a new ephemeral port limit as long as it uses a different interface. This should let my connection counts grow.

However, I can't seem to find a way to force haproxy to use eth0 for one backend server definition and eth1 for another. Is it possible to do that, or are there other ways of achieving what I need?

The system in question is running Debian and haproxy 1.4.8 (default on Debian).

I have always been wondering why Windows Installer only allows you to install one program at a time. It is very frustrating not to be able to launch multiple installations, especially when setting up a new installation of Windows. What is the reason for that?

I am running several different Firebird versions (2.0, 2.1) on multiple entry level Windows-based servers with wildly varying hardware. The only matching thing between them is that they are running same home built application with the same database structure.

Lately I've been seeing massive slowdowns on multiple servers. Turns out that database gets corrupted, so each time it breaks, I get to mend, backup and restore the database, and it all is fine for some time (1-2 weeks), and then it repeats once again. Thankfully, I haven't seen any data loss or damage... yet. The thing is that every such downtime results in lost productivity, and often quite some driving for me as some of the databases are in remote locations.

I've been trying to find out what's causing the corruption, but I haven't been able to. The fact that it's running on different hardware hints that it should not be a hardware based problem.

If we rule out hardware issues, I have a bad feeling that it's a bug in Firebird as I'm not doing anything fancy via SQL. Do you have any idea how to find out exactly what's causing the corruption and hopefully fix the problem?

[edit] According to first reply: I get several different problems in firebird.log:

INET/inet_error: read errno = 10054
INET/inet_error: select in packet_receive errno = 10038
Relation has 12 orphan backversions (5 in use) in table LIMITAI (139)
Index 1 is corrupt on page 61700 level 1. File: ..\..\..\src\jrd\validation.cpp, line: 1659 (repeats for multiple pages and index numbers)
Page 50801 is an orphan (repeats for multiple pages)

I'm running Debian on a machine that has limited memory and no option to add swap space. The machine serves as a web and database server. The problem I'm seeing is that when multiple web requests come in, my database stops accepting connections and sometimes even crashes because the system has no more available RAM.

Is it possible to tell Linux to kill specific processes (in my case, Apache) in case another process (in my case, Firebird) requests memory and there is not enough? If it is not possible to do natively, maybe there is some tool to help me achieve this?