Troubleshooting is a form of problem solving, often applied to repair failed products or processes.

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0
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2answers
237 views

How to troubleshoot network from customers perspective?

We have a web application that we host that is customized for multiple customers. Each customer accesses their version of the site via their own custom subdomain. We are running into an issue where ...
2
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1answer
125 views

server hangs randomly without log entries

My physical server hangs randomly and I do not get any log entries during that time. So I let a script run: while true; do date >>/tmp/dates; sleep 1; done & disown After some minutes the ...
0
votes
1answer
618 views

MySQL 5.0 not logging aborted connections in general log

I know there is a bug in MySQL 5.0 which prevents aborted connections from being logged in the error log (http://bugs.mysql.com/bug.php?id=24761). However, aborted connections should still be logged ...
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vote
1answer
108 views

Advice on web server performance troubleshooting is needed

I'm renting a virtual CentOS based server where I have about 5 active sites running. Several months ago I noticed a significant performance degradation in how my sites are running. First symptom was ...
1
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0answers
1k views

How to prevent Windows Server 2008 R2 from automatically shutting down applications?

I have been running various processes over night on a Windows 2008 R2 AMD64 SP1 virtual server share via a VPN connection and remote desktop. Recently, I have been noticing that when I return in the ...
0
votes
2answers
743 views

How can I find out what Zimbra process (specifically “b”) is doing?

My Zimbra mail server (8.0.2 Community Edition) recently started to spawn an interesting process called "b". top - 11:04:44 up 19 days, 18:47, 1 user, load average: 6.25, 6.38, 5.57 Tasks: 131 ...
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votes
2answers
1k views

How do you troubleshoot a PPTP+VPN+RDP freeze-up?

The symptoms are: I am at home. I am trying to dial a PPTP VPN. It connects fine. Pinging from command line in windows shows about a 30% ping success rate when the PPTP vpn is up, 100% ping success ...
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0answers
650 views

How to troubleshoot occasional Apache 500 errors?

I have GET and POST requests, both HTTP 1.0 and 1.1, to diverse URLs, mostly running Wordpress(1), which occasionally fail with a 500(2). No user has ever encountered a 500 themselves, nor have ...
3
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1answer
65 views

Virtual Server HDD shrinks without apparent reason

We have a virtual hosted Linux server, and in the last few months every now and then the HDD shrinks from 400GB down to the exact byte count that is in use. All existing data can be downloaded and ...
0
votes
1answer
920 views

Why my 2nd ip from traceroute is not answering the ping anymore? [closed]

My Internet is really laggy today, I did a tracerout and I realize that I'm having no answer from an ip at the beginning of the traceroute. see: Tracing route to 12.129.202.154 over a maximum of 30 ...
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2answers
1k views

Port in Public IP can't be accessed [closed]

I have a local ip (xxx.xxx.xxx.xxx) and also a public ip (yyy.yyy.yyy.yyy) for my local server. I host a website in the local server on port 5555. I can open my website from the local ip ...
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0answers
70 views

Vserver CentOs 6.4

I have the following problem. I have a server based on CentOS 6.4 is running the Vserver. I did update the kernel to version 2.6.32.14. Unfortunately, after rebooting the server receives the "kernel ...
0
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1answer
33 views

temporary hang with remote shells keeping the connection

We are having some trouble on our machine having Red Hat 6.2 Enterprise. For just about 1 minute this is what happens: during that minute my SSH shell are frozen and we cannot do anything at the ...
11
votes
1answer
1k views

Harddisks falling offline for unknown reason

I have 7 systems running the setup below. Now and then a different disk falls offline, but on closer inspection the disk is good and not faulty and works flawlessly for at least another year. Since ...
1
vote
1answer
282 views

Cisco ASA: Terrible network speed once or twice a day, fine otherwise

I've been trying to get to the bottom of this for a while now and, well, it seems like I can't. We have two servers behind an ASA5505 (software version 8.3) at a datacenter. They run a wide variety of ...
1
vote
1answer
2k views

How can i find out why my web server is refusing traffic from my web proxy?

I have a bit of an odd problem that I can't seem to figure out. I will preface this question with the fact that this exact setup was working just fine, and for some reason has stopped working ...
0
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0answers
337 views

FreeBSD 7 syslog messages: “kernel: 15.xxxxxxxxxxxxxxx too long” (or “too short”)?

I'm experiencing poor performance on an old FreeBSD system and the only anomaly I see so far are syslog messages of the form: Jul 1 12:10:50 myserverXXX kernel: 16.0ccdd219377c0d80 too long Jul 1 ...
2
votes
1answer
3k views

iptables FORWARD port to internal server

I've been struggling with a FORWARD policy that isn't working the way I'd like, and I can't figure out what is causing the session to fail. I hope someone can help. My goal is to forward port 3000 ...
-4
votes
3answers
112 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 ...
-3
votes
2answers
3k views

Alternatives to wireshark? [closed]

What would be a good option to troubleshoot an interaction of browser with a server besides wireshark? I mean being able to see what the browser sends and receives. Is firebug a good alternative or is ...
4
votes
4answers
395 views

Troubleshooting wireless network in a 4000 square feet office

I work for a non-profit organization in a 4000 sf office with 30 staff. All laptops are connected to the network wirelessly. We have one switch (TP-Link TL-SF1008D Ethernet Switch) and three routers ...
2
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1answer
100 views

Is my server toast?

Last night I received an e-mail from mdadm about the possible failure of two drives on my array. The raid array was set up as a 4 2TB drive raid5 with one hot spare. Is this system truly fried? Did ...
-1
votes
1answer
664 views

DHCP Troubleshooting [closed]

I am working at a branch office and have been tasked with changing out the DHCP scope to match the overall corporate IP address scheme. The main office assigned me an IP address range of ...
3
votes
3answers
197 views

huge slowdown in network of 40 nodes when local DNS is up

We have a LAN with ~40 workstations (mostly Windows) and a couple of servers. All of them use an internal DNS (196.168.0.4 running BIND 9.5.0-P2) and a gateway (192.168.0.1 running OpenBSD Packet ...
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3answers
12k views

How do I identify unknown protocols on my Cisco 2811?

I have a misbehaving Cisco 2811. It serves our office of 20 with internet and phones via Call Manager Express. Except that lately the phones aren't working right and internet is choppy. The outside ...
22
votes
3answers
45k views

What is the ibdata1 file in my /var/lib/mysql directory?

Logging in to my Webmin control panel, I noticed that virtually all of my disk space is full. I searched for the ten largest files/ directories on my system and found that a file called ibdata1 is ...
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0answers
198 views

Windows Server 2008 R2: Weekly network failure

Thought I would throw the question on here, as I'm not a seasoned sysadmin... Every Thursday (or there about) at no particular time, the server becomes unresponsive to its usual network operations ...
0
votes
1answer
16k views

Windows “net use” command throwing error, “System error 1909 has occurred” [duplicate]

What is the likely cause of this, if the command is run on Windows Server 2008? It appears that this account is an administrator on this box. I'm running the Windows command line as an administrator ...
2
votes
2answers
310 views

How do I find where packets are coming from that are being blocked by an ACL?

I have an ACL to prevent regular workstations from accessing the management vlan on our switch. Every 5 minutes we get the following log entry: %SEC-6-IPACCESSLOGS: list mgtvlan-acl denied 0.0.0.0 ...
10
votes
4answers
5k views

How to use kdump/crash to investigate an OOM issue?

The problem A server crashed after multiple "Out of memory" messages and I am trying to pinpoint the culprit. If it is in userland - which process. If it is in the kernel - which kernel module. ...
2
votes
4answers
3k views

IBM Xseries 3400 only working while power button holding pressed

I have an IBM xSeries x3400 Intel Xeon server which only works while someone holds in the power button. My server stopped working and I sent it to IBM Service. After a few hours they told me I could ...
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votes
1answer
657 views

Windows Server 2008 Troubleshooting: Server falling over on a timely basis [closed]

All, This is a generic question, and I know it will upset some people, for which I apologise. I have recently taken a new role, and part of that role involves some sysadmin for Windows 2008 Servers ...
2
votes
3answers
6k views

How to change SMP affinity of an IRQ on Ubuntu PV domU inside Xen XCP?

I'd like to change IRQ SMP affinity for reasons, outlined in this question: CPU0 is swamped with eth1 interrupts But I can't — I see Input/output error when I try to write to ...
0
votes
2answers
142 views

unexpected server power off

Once or twice per day I find a server I have powered off with no apparent reason. Info and what I've done until now: Nothing is being reported under /var/log/. Just normal server activity and then ...
2
votes
1answer
464 views

Measure Upload Speed between a client and our server

We host a SAAS application specially customized for multiple clients. For one customer in particular -- they are reporting sporadic performance issues from various locations on their network, in ...
0
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1answer
373 views

Troubleshoot IIS 6 and Intermittent SQL Server Connectivity Loss

I am not a System Administrator, but I am temporarily trying to fill that role. I have 2 Windows 2003 Servers. 1 server has my Microsoft SQL Database (SQL Server 2005) and the other is the web ...
1
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0answers
288 views

Apache taking up a lot of CPU while running request-tracker4

I am trying out a request-tracker installation on an EC2 micro instance. The specs for the micro instance are as follows 1) Ubuntu 12.04 64bit, 613MB RAM, 8GB Hard Drive 2) Running request-tracker ...
0
votes
1answer
506 views

Diagnosing SAN connectivity issues (RHEL5)

We are currently utilizing GFS2 to share a SAN LUN between 3 servers. However due to a feature problem with vendor software we are using, we currently have the volume unmounted on two of the boxes, ...
0
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4answers
2k views

Server freeze - how to debug

I am running a Debian virtual server with Apache, PHP, MySQL. There is just 1 website with very low traffic running but the server very often (almost everyday) freezes and does not respond. When ...
3
votes
1answer
2k views

Troubleshooting Windows Server 2012 storage spaces

I'm trying the new "Storage Pools" feature on Windows Server 2012, and I've created several disks on the pool. When I restart the server, some of the disks (two, out of four) do not attach ...
0
votes
1answer
300 views

How can I easily test connectivity to external sources with WinHTTP?

I've got an server application that uses Winhttp to fetch information from an external source. Occasionally, I'll need to troubleshoot connectivity issues and I'd like an easy way to test connections ...
0
votes
1answer
387 views

Windows Server 2008 R2 Troubleshooting PID Leaking

One of our servers has been leaking PID like crazy. I wrote a simple scheduled script, and it seems that every day the highest PID increases by approx. 300'000. E.g., if on Aug.24 00:00 the highest ...
1
vote
1answer
373 views

What are some steps to trouble shoot denied HTTPS requests in IIS 7?

I'm hosting a site in IIS 7 that's using a wildcard certificate from RapidSSL. To date there's been no issues of people not being able to connect to the site with SSL. Now we have a client who can't ...
1
vote
1answer
142 views

ASP.NET error logging locations and troubleshooting

Say an ASP.NET website suddenly starts returning a 500 error code with a blank page (not serving the configured error document). Where might I find error reports and/or clues as to what is happening, ...
3
votes
1answer
2k views

Odd one-way ping issue that I can't wrap my head around

Long time lurker, but today I encountered an odd problem that will bug me until resolution :-) It seems to be presenting as a one-way ping issue from one server to a failover cluster. All machines ...
5
votes
3answers
19k views

Troubleshooting Windows EAP/RADIUS connectivity issues

So, I guess the short version of the question is: I'm unable to get clients to connect to an enterprise-WPA wireless network after setting up a "new" NPS server and a new CA. After I manually ...
0
votes
2answers
194 views

Server unresponsive, messages shown on console but not in log files

I'm using Ubuntu Server 10.04.4, and once in a while the server hangs (once a month) and is totally unresponsive. The tty is flooded with messages like these. The problem is that these messages are ...
1
vote
1answer
3k views

“Device not ready” on a network share in Windows 7

I have two computers C1 and C2 runing Windows 7 and both of them are members in a domain. On C1 I have an USB hard-disk which I shared for the users U1 and U2 giving them Read-Only permissions on the ...
0
votes
1answer
56 views

How to troubleshoot banned connections on OS X / Ubuntu

I have an ubuntu 11.10 VM running on an OSX machine. Every once in a while some services become inaccessible from specific IPs (e.g. sometimes just ssh is blocked, and sometimes both ssh and https.) ...
5
votes
3answers
36k views

How to investigate unexpected Linux server shut down?

In a new Xeon 55XX server with 4xSSD at raid 10 with Debian 6, I have experienced 2 random shut downs within two weeks after the server being built. Looking at bandwidth logs before shut down does not ...