Finding problems in a program and trying to solve these.

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1
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2answers
79 views

bizarre 404 on nginx

i have a location block for / that passes any virtual paths to index.php as instructed on the nginx pitfalls page. i have been using this setup for some time now, but recently i have noticed that some ...
0
votes
0answers
18 views

Drupal on Apache: Consecutive PHP errors “Maximum execution time of 240 seconds exeeded”

This Apache/MySQL server (Debian 8) running a Drupal site shows a strange behaviour: There's always one Apache process running with 100% CPU utilization (according to htop). Every four minutes (~240 ...
3
votes
1answer
1k views

SQL Server Debugging: “Unable to Step. Invalid operation”

I'm debugging a call to a Stored Procedure in SSMS (2012). Frequently, and various random points in the code, a dialog pops up: Microsoft SQL Server Management Studio: Unable to Step. Invalid ...
33
votes
6answers
13k views

Debugger for Iptables

I'm looking for an easy way to follow a packet through the iptables rules. This is not so much about logging, because I don't want to log all traffic (and I only want to have LOG targets for very few ...
0
votes
1answer
36 views

Log all bash actions with multiple scripts

Using the command below, I can log all actions that happened inside that script. bash -x script.sh Sadly, the script calls another script, which does not have the -x setting active then, i.e. the ...
1
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0answers
29 views

debugging “eth interface using wrong IP” on server

My Uni provided me two hostnames and static IPs for two interfaces on my Fedora Server 23. My idea is to use one hostname for production and another for dev branches. It should work as: bio-db.uni.edu ...
1
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0answers
19 views

Obtaining a Crash Dump from a dying IIS ASP.NET Worker Process

(Not sure if this is an IIS problem or not, so if this is better suited for SO I'll happily move it...) We have an IIS-hosted application that is sporadically dying, and the event logs claim that the ...
2
votes
1answer
22 views

Verifying RADIUS server is sending the correct certificates?

How can I see the TLS (SSL) certificates that my RADIUS server is using, to make sure it is sending the correct certificate and chain? I am implementing 802.1x authentication with a RADIUS server, ...
1
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3answers
1k views

Getting debug output from a debian initramfs

I'm attempting to configure a server for a debian lenny on software raid0 and a LVM root filesystem via the serial console and the hosting company's recovery console (basically an ubuntu liveCD). ...
4
votes
0answers
909 views

How to debug CGI over fcgiwrap/nginx

I serve executable scripts (mainly in C) through fcgiwrap connected with nginx. Since the scripts are complied, I can get the coding errors during compilation, but sometimes I receive CGI errors ...
0
votes
1answer
69 views

Occasional “failed to respond” from AWS hosted Elasticsearch

We have an Elasticsearch cluster hosted on Amazon Elasticsearch Service (AWS). We are using the Jest Java HTTP Rest client for ElasticSearch. Every now and then (perhaps 1 in 10,000 requests), it ...
0
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0answers
20 views

“error establishing a database connection” On my wordpress website - with indexes problems?

I keep getting this: "error establishing a database connection" and this is not ending. This is /var/log/apache2/error.log: [Thu Mar 31 11:38:45.865505 2016] [autoindex:error] [pid 22782] [...
0
votes
0answers
17 views

How to debug lost connections

I'm having a problem between a computer running Filemaker Server and their clients: clients loose the connection often (3-4 times per day), even when the user is using it (so no disconnect on idle). ...
0
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0answers
17 views

IPTables debugging

I've got a weird problem. I've got a primary host in Nevada and a satellite site in Maryland. They both use the 192.168.21.0/24 subnet (as well as .18.0 and .101.0) and have some overlapping addresses....
3
votes
3answers
10k views

How do I identify slow queries in sql server?

I've found long, complicated instructions like this when googling for the answer to this question, an brief reference links such as in this post. I'm looking for a succinct a procedure as possible to ...
16
votes
4answers
21k views

How can I find out what is causing interrupts on Windows?

Occasionally I come across servers (Windows 2003 and 2008) with high processor % interrupt time. Is there a way to see what program or device is causing the interrupts?
2
votes
0answers
37 views

How to reliably capture Linux kernel log messages in case of a system debilitating crash (BUG, panic)?

I'd like to have access to the lines/tracebacks/whatever whispered by the kernel right before dying. This has proven problematic, because all interfaces I have access to become disabled. Post-reboot, ...
-4
votes
3answers
116 views

How to debug and prevent flaky unreliable IT environment? [closed]

I am not an IT admin, I'm a software developer (microsoft stack) and I'm trying to understand what is wrong with the IT environment of one of our customers. We have deployed our client\server ...
0
votes
0answers
72 views

Troubleshooting with kernel call trace and underlying root cause with XFS

How to determine the root underlying cause of an error when looking through a Linux kernel call trace, and in which order should I read the call trace? From my understanding, the call trace should ...
0
votes
0answers
15 views

client sends password instead of userid when authenticating to Exim

I have an unusual problem and am not sure how to debug it. I am running exim4 on debian with client authentication set to plain over TLS. This is a family/business server I have a few friends who ...
1
vote
0answers
12 views

Show or log long queries with values instead placeholders

I have any very long sql query in postgresql. I tried show what postgress do with: select * from pg_stat_activity unfortunately I see something like: select some_fields from anytable1 anytable2 ...
0
votes
1answer
22 views

Debug Logging daily task

I manage a domain with 4 domain controllers and i have been asked to enable Debug Logging for Incoming and Request packets. I have set the maximum size of the log file to 500MB. First question I have,...
4
votes
3answers
1k views

Send bash -x output to logfile without interupting standard output

Is there a way to send the information displayed by running a bash script with the -x option to a file, while not changing the standard output seen by a user running the script? This is a debugging ...
9
votes
8answers
5k views

Equivalent of SysInternals FileMon for Linux?

I'm attempting to debug an application on Ubuntu - I need to listen to file open attempts (even for files that don't exist). Process Monitor (formerly known as FileMon) is available on Windows - what'...
1
vote
0answers
74 views

ProcessMonitor boot logging claims disk is full

I'm trying to debug an issue where Windows 7 logoff will hang about once in every 5-10 logoffs forcing a hard reboot. I've installed Process Monitor (v3.2) and am running boot logging to try and find ...
4
votes
4answers
5k views

Failed Request Tracing XML fails to display in Internet Explorer (IIS 7.5)

I have installed the Tracing feature and enabled failed request tracing for a website, to debug a Classic ASP website. The XML logs are created upon occurring errors, however when I open them in IE, ...
6
votes
1answer
942 views

How to configure PHPStorm to debug on IIS

I installed PHP 5 on IIS on a Windows 7 64 bit machine using the Web Platform Installer. I am using PHPStorm as my PHP IDE but cant find any documentation on how to get debugging to work. PHPStorm ...
3
votes
3answers
58 views

debugger in bash

I use sh -xv my_script.sh to debug the /bin/sh script. How do I debug /bin/bash scripts? I am getting the following error and I need to know the line that needs to edit. # ./batch_master.sh '@'...
1
vote
1answer
44 views

Server frequently hangs, my client wants me to do X while the proper solution is Y

This question is more on etiquette rather than an actual server issue. 2 servers owned by a client of mine frequently stop responding (Fast, then really sluggish as in it takes 1 minute to execute ls,...
1
vote
2answers
247 views

Where (and how) to put PDB files for custom .NET code?

Our developer sent me a PDB file to help debug a custom application. I currently have my symbol directory set to c:\symbols, and several Microsoft symbols are there in this folder format: ntdll.pdb ...
0
votes
1answer
473 views

What are the first steps to debug nginx default page not showing on fresh Ubuntu vm install?

On a fresh Ubuntu 14.04 virtual machine I've run the following commands: sudo apt-get update sudo apt-get upgrade sudo apt-get install nginx sudo service nginx start In a browser, if I go to the ...
3
votes
1answer
6k views

Debug 500 Internal Server Error on IIS

Might be a n00b question. I have an IIS server with a site where I can host our website. But if I host the same website as an application in an existing site, it gives us a 500 error. But my ...
14
votes
3answers
33k views

Debugging rules in Iptables [duplicate]

How can I know how many packets were dropped by my iptables rules ?? Is there any debugging mechanism to see which rule is Dropping my packet or Accepting it ??
1
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0answers
92 views

CoreOS Random Reboot Kernel Panic with Obscure Message - How to debug?

I'm relatively new to the CoreOS world, we had a server reboot and the messaging in the Journal is extremely vague: Sep 18 07:10:27 ip-x-x-x-x.us-west-2.compute.internal kernel: BUG: unable to handle ...
2
votes
1answer
440 views

What steps are required to debug a memory.dmp? (walkthrough included)

I woke up to this in my eventlog today: The computer has rebooted from a bugcheck. The bugcheck was: 0x000000ef (0xffffe0018668f080, 0x0000000000000000, 0x0000000000000000, 0x0000000000000000). A ...
25
votes
9answers
19k views

How to setup a fake SMTP server to catch all mails?

I'm looking for an smtp service that essentially obeys the RFC, except rather than sending mail it simply logs to a file [date] sent mail to <address> Or whatever. I can bash this together ...
0
votes
1answer
2k views

Should I expect ICMP transit traffic to show up when using debug ip packet with a mask on a Cisco IOS router?

So I am trying to trace an ICMP conversation between 192.168.100.230/32 an EZVPN interface (Virtual-Access 3) and 192.168.100.20 on BVI4. # sh ip access-lists 199 10 permit icmp 192.168.100.0 0.0....
1
vote
1answer
278 views

Tracking down a memory leak

I previously asked a question about a server that had a very high nonpaged pool memory utilization and someone explained how to use poolmon to track down the problem driver. I did this, but I'm not ...
-1
votes
1answer
196 views

Tons of 500 errors like - fcgid:warn Bad file descriptor: client mod_fcgid: ap_pass_brigade failed in handle_request_ipc function

I copied a site over to GoDaddy from LiquidWeb because LW experts were unhelpful even if more knowledgeable. GD is hit or miss. On the Godaddy hosting I get 500 errors constantly when in admin ...
4
votes
2answers
3k views

How to trace Apache 301 Moved Permanently?

I have one virtual host on my machine, which I am accessing localy. I am running apache2 under windows 7. When accessing this host, I see in Fiddler, that server redirects browser to different remote ...
0
votes
0answers
44 views

Error with a specific bash script

I must first of all shamefully admit that I unfortunately know nothing about scripts... I am simply trying to use one that seems to fit my goal. I am running a VPS node with OpenVZ, and I need a ...
0
votes
1answer
168 views

Debugging random SQL login failure from Web Server

This is a very basic level question, but it could really benefit from some extra help in the diagnosis. We have a 2005 SQL Server Named: SERVERNAME-PROD We have a Web Apps Server that's running IIS 8....
0
votes
1answer
846 views

Linux kernel bug w/ netns and/or Xen guest - “unregister_netdevice: waiting for lo to become free”

I am running a web crawler in a Xen-based VM (on Linode); it makes heavy use of network namespaces to control use of VPNs on a per-crawl-process basis. It's been running mostly continuously for the ...
0
votes
1answer
71 views

Installation of FreeBSD freezes on VMware

I am trying to install FreeBSD on VMware by mounting FreeBSD-9.2-RELEASE-i386-dvd1.iso. The installation proceeds fine untill i reach the following screen I have been waiting for an hour and ...
-1
votes
2answers
39 views

Querying a webserver as if request came from a certain remote IP?

I am having trouble with my Apache web server configuration since a number of remote clients receive 404s, while the majority of clients (me, locally, included) do not have any trouble (status 200). ...
4
votes
2answers
14k views

All connections from this network get stuck in SYN_RECV state, connections from my home or phone properly get ESTABLISHED

My server (a linode VPS) suddenly started to timeout on every request yesterday. I'm pretty inexperienced in networking and would love to learn a process for debugging these connectivity issues. ...
1
vote
1answer
223 views

APC resets after a few seconds

Got a new server and the host installed APC for me. Reloading apc.php shows that ACP resets itself every 4-6 seconds. Uptime is always 0 and hits never go above 3000. The site runs smoothly but if ...
6
votes
4answers
1k views

How to pinpoint which process/activity/software/protocol is slowing down LAN on a single computer

From this question about debugging our business LAN I've been able to pinpoint a single computer which slows down our network. When the computer is turned on and connected to the network, roughly 5% ...
1
vote
2answers
99 views

How to pinpoint why a specific ressource (image or library) slowing down page load

We have a small network (maybe 15 users at top business hours, around 30 devices) managing internet connection and phone lines. The primary use of the network is for users to access the web based ...
4
votes
1answer
3k views

How to debug Node + Socket.io CPU Issues

We are running a Node Socket.io server with Express 3. The server is monitored using Forever. The service is running well, but the CPU grows throughout the day, until it reaches 90%+ and then suddenly ...