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  • Distributed File Systems.

    - by GruffTech
    So, I've been reading several articles around ServerFault as well as google. (For Example, this link) My Requirements are very similar to the link above, however i'd like to also have dynamic or at least resizeable file volumes, so if necessary i can add 4-5 servers to the pool, and then expand the volume. Any Distributed File systems that support that, to save me some time? Thanks! LustreFS will be my next test cluster to build. GlusterFS I've build a 3-machine test GlusterFS cluster, However i quickly became aware of several of its limitations that it doesn't seem to make clearly public. One, i can't seem to resize a volume. Once a volume is created, its done. Which seems retarded, why have a fully scalable file system if i can't scale a volume? So maybe i'm doing something wrong. I'm not sure. AmazonS3 while gives the cheapest startup adds too much cost when broken down to per client per month, so its out. Building my own system when prorated over several years with no bandwidth costs makes it significantly cheaper. MogileFS isn't an option as we'd like this server to be a SAN-Replacement, for storing tons of media from a multitude of systems, which for us means it needs to be POSIX compliant so it can be remotely mounted via NFS or CIFS.

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  • Recommendation on remote access setup for accessing customer systems

    - by gregmac
    I'm looking for a product recommendation (open or commercial) that will allow remote access to customer sites for tech support purposes. We need to be able to gain access to help troubleshoot problems on servers. Currently end up using anything from RDP on public IP, to various VPNs that clients happen to have, to webex-type sessions that require lots of interaction from both sides to get things working. This often means a problem that could take 10 minutes to solve takes an extra 30+ minutes messing around trying to get a connection up. There are multiple customer sites, which should NOT have access to each other. At each site, there is anywhere from 1 to 8 servers (Windows 2003 or 2008) that need to be accessed. Support connection to machines even if they're behind a firewall/router with no public IP Be able to selectively allow/deny access from customer site. Customer site should not be able to connect outbound to anywhere else (our systems, or other customer sites) Support multiple users from our end If not a VPN connection (where RDP could be used over top), should support: Remote desktop access, including copy/paste File transfers Preferably would have some way to list all remote systems, showing online/offline. Anyone have any suggestions?

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  • Examples of limitations in IT due to different bit length by design

    - by Alaudo
    I am teaching the course "Introduction in Programming" for the first-year students and would like to find interesting examples where the datatype size in bits, chosen by design, led to certain known restrictions or important values. Here are some examples: Due to the fact that the Bell teleprinter used 7-bit-code (later accepted as ASCII) until now have we often to encode attachments in electronic messages to contain only 7 bit data. Classical limitation of 32-bit address space leads to the 4Gb maximal RAM size available for 32-bit systems and 4Gb maximal file size in FAT32. Do you know some other interesting examples how the choice of the data type (and especially its binary length) influenced the modern IT world. Added after some discussion in comments: I am not going to teach how to overcome limitations. I just want them to know that 1 byte can hold the values from -127..0..+127 o 0..255, 2 bytes cover the range 0..65535 etc by proving examples they know from other sources, like the above-mentioned base64 encoding etc. We are just learning the basic datatypes and I am trying to find a good reference for "how large" these types are.

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  • Moving From IT to Embedded software Developing

    - by Ameer Adel
    i worked for two years at a channel station, managing various Types of tasks, varying from printers installation, software solution, down to managing and maintaining server automation, to be honest, i always been enthusiastic about programming, i studied at some affordable college and finished my IT path successfully, my graduation project was in C# ADO.NET couple of years ago. Obviously it was so much of a beginner spaghetti code than a well furnished code. I also had the chance; after leaving the IT career, to study about some ASP.NET MVC and web apps development. I have rookie level of coding skills due to the poor level of education i endured, and sufficient resources. Currently i m working as a trainee in a newly opened embedded software development company, that is being said, i am, as i sound, have a little idea about the algorithms included, as i was reading for the past couple of days, embedded system development requires more strict coding skills, including memory management, CPU optimization according to its architect, and couple of other tricks regarding the display, and power management if mobile.. etc. My question is, What type of Algorithms am i supposed to use in such cases, as i mentioned before, i am really enthusiastic about learning programming skills and algorithms related to embedded systems and programming languages, including C/C++, Java, C#, and some EC++ if still operational.

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  • What Computing/Programming Qualifications should I aspire for

    - by indevel
    I am a computing science post graduate in my first job from after my degree. During my 12 month review my boss posed the question "What can we do for you in terms of progressing your career?". This got me thinking, after university I hadn't really thought about what other qualifications were available. So this is my question, what courses/qualifications should I be looking to do. Which are highly regarded and which would be really useful to complete. I've searched Google it but all I see is a jumble of courses with no idea of the credibility of each. Any help is much appreciated. I'm traditionally a systems architect, but with this job I've turned to more embedded work so Id like to edge towards electronics, embedded programming, real time OS to help with my work also it would be more likely to be accepted if it was related to my job. Finally UK based courses/ qualifications are a must as travel is probably out of the question. Help me grow as a programmer.

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  • Android Signal analysis + some filters.

    - by Profete162
    Hello, as the world cup is the main sport event and the Vuvuzelas are the most annoying sound in the world, I had an idea to remove them definitively by reading this new ( http://www.popsci.com/diy/article/2010-06/simple-software-can-filter-out-vuvuzela-whine) that told us that the sound has some frequencies at 233Hz + 466,932,1864Hz. I have already made a lot of Android application by myself but never touching the signal analysis and filtering part, so here are a few questions, I do not ask for precise answer but maybe links and tutorial to find something to work on. I guess that a new Android phone has the CPU and power to make real-time filtering. 1) How can I intercept the sound coming from the Jack microphone - Line-IN plug- ( I plan to link my TV to my phone with Jack to Jack plug). My question is totally software and coding, I have all the wires and adapters to plug a jack into my android phone Line IN. 2) Are there some Fourier analysis librairies, may I have a look to Java libraries on the web and import them to my Android project? I really apologize because my question seem not precise, but I think that would be something great. Thank you for your answers.

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  • Statistical analysis on large data set to be published on the web

    - by dassouki
    I have a non-computer related data logger, that collects data from the field. This data is stored as text files, and I manually lump the files together and organize them. The current format is through a csv file per year per logger. Each file is around 4,000,000 lines x 7 loggers x 5 years = a lot of data. some of the data is organized as bins item_type, item_class, item_dimension_class, and other data is more unique, such as item_weight, item_color, date_collected, and so on ... Currently, I do statistical analysis on the data using a python/numpy/matplotlib program I wrote. It works fine, but the problem is, I'm the only one who can use it, since it and the data live on my computer. I'd like to publish the data on the web using a postgres db; however, I need to find or implement a statistical tool that'll take a large postgres table, and return statistical results within an adequate time frame. I'm not familiar with python for the web; however, I'm proficient with PHP on the web side, and python on the offline side. users should be allowed to create their own histograms, data analysis. For example, a user can search for all items that are blue shipped between week x and week y, while another user can search for sort the weight distribution of all items by hour for all year long. I was thinking of creating and indexing my own statistical tools, or automate the process somehow to emulate most queries. This seemed inefficient. I'm looking forward to hearing your ideas Thanks

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  • Willy Rotstein on Analytics and Social Media in Retail

    - by sarah.taylor(at)oracle.com
    Recently I came across a presentation from Dan Zarrella on "The Science of Retweets. (http://www.slideshare.net/HubSpot/the-science-of-retweets-with-dan-zarrella). It is an insightful, fact-based analysis of how tweets propagate and what makes them successful. The analysis is of course very interesting for those of us interested Tweeting. However, what really caught my attention is how well it illustrates, form a very different angle, some of the issues I am discussing with retailers these days. In particular the opportunities that e-commerce and social media open to those retailers with the appetite and vision to tackle the associated analytical challenges. And these challenges are of course not straightforward.   In his presentation Dan introduces the concept of Observability, I haven't had the opportunity to discuss with Dan his specific definition for the term. However, in practical retail terms, I would say that it means that through social media (and other web channels such as search) we can analyze and track processes by measuring Indicators that were not measurable before. The focus is in identifying patterns across a large number of consumers rather than what a particular individual "Likes".   The potential impact for retailers is huge. It opens the opportunity to monitor changes in consumer preference  and plan the business accordingly. And you can do this almost "real time" rather than through infrequent surveys that provide a "rear view" picture of your consumer behaviour. For instance, you could envision identifying when a particular set of fashion styles are breaking out from the pack, and commit a re-buy. Or you could monitor when the preference for a specific mobile device has declined and hence markdowns should be considered; or how demand for a specific ready-made food typically flows across regions and manage the inventory accordingly. Search, blogging, website and store data may need to be considered in identifying these trends. The data volumes involved are huge (check Andrea Morgan's recent post on "Big Data" in retail) but so are the benefits. As Andrea says, for the first time we can start getting insight into "Why" the business is performing in a certain way rather than just reporting on what is happening. And it is not just about the data volumes. Tackling the challenge also calls for integrated planning systems that can bring data and insight into the context of the Decision Making process Buyers, Merchandisers and Supply Chain managers are following. I strongly believe that only when data and process come together you can move from the anecdotal to systematically improving business performance.   I would love to hear your opinions on these trends and where you think Retail is heading to exploit these topics - please email me: [email protected]

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  • #SSAS #Tabular Workshop and Community Events in Netherlands and Denmark

    - by Marco Russo (SQLBI)
    Next week I will finally start the roadshow of the SSAS Tabular Workshop, a 2-day seminar about the new BISM Tabular model for Analysis Services that has been introduced in SQL Server 2012. During these roadshows, we always try to arrange some speeches at local community events in the evening - we already defined for Copenhagen, we have some logistic issue in Amsterdam that we're trying to solve. Here is the timetable: Netherlands SSAS Workshop in Amsterdam, NL – April 16-17, 2012 2-day seminar, I and Alberto will be the trainers for this event, register here We're trying to manage a Community event but we still don't have a confirmation, stay tuned        Denmark SSAS Workshop in Copenhagen, DK – April 26-27, 2012 2-day seminar, I and Alberto will be the trainers for this event, register here Community event on April 26, 2012 This event will run in Hellerup, at Microsoft venue All details available here: http://msbip.dk/events/26/msbip-mode-nr-5/ People from Sweden are welcome! Just register to this private group on LinkedIn in order to announce your presence, so we’ll know how many people will attend In community events we’ll deliver two speeches – here are the descriptions: Inside xVelocity (VertiPaq) PowerPivot and BISM Tabular models in Analysis Services share a great columnar-based database engine called xVelocity in-memory analytics engine (VertiPaq). If you want to improve performance and optimize memory used, you have to understand some basic principles about how this engine works, how data is compressed, and how you can design a data model for better optimization. Prepare yourself to change your mind. xVelocity optimization techniques might seem counterintuitive and are absolutely different than OLAP and SQL ones! Choosing between Tabular and Multidimensional You have a new project and you have to make an important decision upfront. Should you use Tabular or Multidimensional? It is not easy to answer, because sometime there is a clear choice, but most of the times both decisions might be correct, at least at the beginning. In this session we’ll help you making an informed decision, correctly evaluating pros and cons of each one according to common scenarios, considering both short-term and long-term consequences of your choice. I hope to meet many people in this first dates. We have many other events coming in May and June, including an online event (for US time zones), and you can also attend our PreCon Day at TechEd US in Orland (PRC06) or TechEd Europe in Amsterdam. I’ll be a good customer for airline companies in the next three months! I’m just sorry that I hadn’t time to write other articles in the last month, but I’m accumulating material that I will need to write down during some flight – stay tuned…

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  • RoboCopy Log File Analysis

    - by BobJim
    Is it possible to analyse the log text file outputted from RoboCopy and extract the lines which are defined as "New Dir" and "Extra Dir"? I would like the line from the log contain all the details returned regarding this "New Dir" or "Extra Dir" The reason for completing this task is to understand how two folder structures have change over time. One version has been kept internally at the parent company, the second has been used by a consultancy. For your information I am using Windows 7.

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  • Excel techniques for perfmon csv log file analysis

    - by Aszurom
    I have perfmon running against several servers, where I'm outputting to a .csv file data like CPU %time, memory bytes free, hard disk I/O metrics like s/write and writes/s. The ones graphing the SQL servers are also collecting SQL stats. The web servers are collecting .Net relevant stuff. I am aware of PAL, and used it as a template of what data to capture based on server type actually. I just don't think the output it generates is detailed or flexible enough - but it does a pretty remarkable job of parsing logs and making graphs. I'm borderline incompetent with Excel, so I'm hoping to be directed to some knowledge of how to take a perfmon output .csv and mine it in Excel to produce some numbers that are meaningful to me as a sysadmin. I could of course just pick a range of data and assemble a graph out of that and look for spikes and trends, but I'm convinced there is some technique to this that makes it more manageable than looking at a monsterous spreadsheet of numbers and trying to make graphs of it. Plus, it's pretty time consuming and not something I can do as a "take a glance at the servers" sort of routine. I'm graphing CPU, disk use, network b/sec, etc. in Cacti as well, which is nice for seeing big trends. The problem is that it is 5 minute averages, so a server could have a problem but it's intermittent and washes out in a 5 min average. What do you do with perfmon data that I could learn from?

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  • Linux installation analysis

    - by blunders
    "Ending company IT Admin relationship" has a good checklist for taking over an existing IT system, but I'm wondering as it relates to Linux: What is the most effective way to assess the scope of existing custom configurations, installs, scripts, etc done? Is there any software that will check if the kernel, system files, etc mirror the default files for the version installed? At this point I don't know what distro of Linux the server (though using Netcraft I do know the server appears to be Linux) -- so it's possible without knowing that information that this would be a hard question to answer.

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  • MySql Data Loss - post mortem analysis - RackSpace Cloud Server

    - by marfarma
    After a recent 'emergency migration' of a RS cloud server, the mysql databases on our server snapshot image proved to be days out of date from the backup date. And yet files that were uploaded through the impacted webapp had been written to the file system. Related metadata that was written to the database was lost, but the files themselves were backed-up. Once I was able to manually access the mysql data files before the mysql server started (server was configured to start mysql on boot), I was able to see that the update time for ib_logfile1, ib_logfile0 and ibdata1 was days old. As with this poster, mysql data loss after server crash, it's as if some caching controller had told the OS / mysql server that it had committed data that was still in cache, and it was lost instead of flushed. I can't quite wrap my head around how the uploaded files got written but the database data did not. I would have thought that any cache would have flushed system wide, rather than process by process. Any suggestions as to how this might have happened?

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  • Windows File System Analysis

    - by bouvierr
    I am looking for a FREE tool to perform analyses on the NTFS file system of my Windows 7 PC. I want to easily see the amount of data distributed throught out the entire file system. The following applications seem very good, but they are not free and probably overkill for my requirements: FolderSizes 5 MailMeter Windows File System Reporting Tool I am aware that some applications (like Folder Size 2.5) can add a column in Windows Explorer to show the size of each folder, but I am looking for something more like a reporting tool. Thank you for your suggestions.

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  • Server hang - data loss on reboot, post mortem analysis

    - by rovangju
    A development server I'm responsible for (ext3 on raid 5 w/Debian Squeeze) froze up over the weekend and I was forced to reset it, as in unresponsive from KVM/physical keyboard access, no eth devices responding, etc. Not even the backup process ran (Figures, the one time I don't check for confirmation) So after the reset, it turns out that every trace of disk IO activity that should have happened for a period of ~24H is completely gone. The log files have a big gap in the dates and times. As if the writes were never committed to disk, no processes seemed to have run. Luckily it was a weekend and nothing of value would have been lost and I don't suspect a hack. What can I do in post mortem to this event - to prevent it from ever happening again? I've seen this happen before on a completely different machine running FreeBSD. I am rounding up the disk checking tools right now - but there must be more going on! Mount options: /dev/sda1 on / type ext3 (rw,errors=remount-ro) Kernel: Linux dev 2.6.32-5-686-bigmem Disk/Inodes: 13%/3%

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  • Forensic Analysis of the OOM-Killer

    - by Oddthinking
    Ubuntu's Out-Of-Memory Killer wreaked havoc on my server, quietly assassinating my applications, sendmail, apache and others. I've managed to learn what the OOM Killer is, and about its "badness" rules. While my machine is small, my applications are even smaller, and typically only half of my physical memory is in use, let alone swap-space, so I was surprised. I am trying to work out the culprit, but I don't know how to read the OOM-Killer logs. Can anyone please point me to a tutorial on how to read the data in the logs (what are ve, free and gen?), or help me parse these logs? Apr 20 20:03:27 EL135 kernel: kill_signal(13516.0): selecting to kill, queued 0, seq 1, exc 2326 0 goal 2326 0... Apr 20 20:03:27 EL135 kernel: kill_signal(13516.0): task ebb0c6f0, thg d33a1b00, sig 1 Apr 20 20:03:27 EL135 kernel: kill_signal(13516.0): selected 1, signalled 1, queued 1, seq 1, exc 2326 0 red 61795 745 Apr 20 20:03:27 EL135 kernel: kill_signal(13516.0): selecting to kill, queued 0, seq 2, exc 122 0 goal 383 0... Apr 20 20:03:27 EL135 kernel: kill_signal(13516.0): task ebb0c6f0, thg d33a1b00, sig 1 Apr 20 20:03:27 EL135 kernel: kill_signal(13516.0): selected 1, signalled 1, queued 1, seq 2, exc 383 0 red 61795 745 Apr 20 20:03:27 EL135 kernel: kill_signal(13516.0): task ebb0c6f0, thg d33a1b00, sig 2 Apr 20 20:03:27 EL135 kernel: OOM killed process watchdog (pid=14490, ve=13516) exited, free=43104 gen=24501. Apr 20 20:03:27 EL135 kernel: OOM killed process tail (pid=4457, ve=13516) exited, free=43104 gen=24502. Apr 20 20:03:27 EL135 kernel: OOM killed process ntpd (pid=10816, ve=13516) exited, free=43104 gen=24503. Apr 20 20:03:27 EL135 kernel: OOM killed process tail (pid=27401, ve=13516) exited, free=43104 gen=24504. Apr 20 20:03:27 EL135 kernel: OOM killed process tail (pid=29009, ve=13516) exited, free=43104 gen=24505. Apr 20 20:03:27 EL135 kernel: OOM killed process apache2 (pid=10557, ve=13516) exited, free=49552 gen=24506. Apr 20 20:03:27 EL135 kernel: OOM killed process apache2 (pid=24983, ve=13516) exited, free=53117 gen=24507. Apr 20 20:03:27 EL135 kernel: OOM killed process apache2 (pid=29129, ve=13516) exited, free=68493 gen=24508. Apr 20 20:03:27 EL135 kernel: OOM killed process sendmail-mta (pid=941, ve=13516) exited, free=68803 gen=24509. Apr 20 20:03:27 EL135 kernel: OOM killed process tail (pid=12418, ve=13516) exited, free=69330 gen=24510. Apr 20 20:03:27 EL135 kernel: OOM killed process python (pid=22953, ve=13516) exited, free=72275 gen=24511. Apr 20 20:03:27 EL135 kernel: OOM killed process apache2 (pid=6624, ve=13516) exited, free=76398 gen=24512. Apr 20 20:03:27 EL135 kernel: OOM killed process python (pid=23317, ve=13516) exited, free=94285 gen=24513. Apr 20 20:03:27 EL135 kernel: OOM killed process tail (pid=29030, ve=13516) exited, free=95339 gen=24514. Apr 20 20:03:28 EL135 kernel: OOM killed process apache2 (pid=20583, ve=13516) exited, free=101663 gen=24515. Apr 20 20:03:28 EL135 kernel: OOM killed process logger (pid=12894, ve=13516) exited, free=101694 gen=24516. Apr 20 20:03:28 EL135 kernel: OOM killed process bash (pid=21119, ve=13516) exited, free=101849 gen=24517. Apr 20 20:03:28 EL135 kernel: OOM killed process atd (pid=991, ve=13516) exited, free=101880 gen=24518. Apr 20 20:03:28 EL135 kernel: OOM killed process apache2 (pid=14649, ve=13516) exited, free=102748 gen=24519. Apr 20 20:03:28 EL135 kernel: OOM killed process grep (pid=21375, ve=13516) exited, free=132167 gen=24520. Apr 20 20:03:57 EL135 kernel: kill_signal(13516.0): selecting to kill, queued 0, seq 4, exc 4215 0 goal 4826 0... Apr 20 20:03:57 EL135 kernel: kill_signal(13516.0): task ede29370, thg df98b880, sig 1 Apr 20 20:03:57 EL135 kernel: kill_signal(13516.0): selected 1, signalled 1, queued 1, seq 4, exc 4826 0 red 189481 331 Apr 20 20:03:57 EL135 kernel: kill_signal(13516.0): task ede29370, thg df98b880, sig 2 Apr 20 20:04:53 EL135 kernel: kill_signal(13516.0): selecting to kill, queued 0, seq 5, exc 3564 0 goal 3564 0... Apr 20 20:04:53 EL135 kernel: kill_signal(13516.0): task c6c90110, thg cdb1a100, sig 1 Apr 20 20:04:53 EL135 kernel: kill_signal(13516.0): selected 1, signalled 1, queued 1, seq 5, exc 3564 0 red 189481 331 Apr 20 20:04:53 EL135 kernel: kill_signal(13516.0): task c6c90110, thg cdb1a100, sig 2 Apr 20 20:07:14 EL135 kernel: kill_signal(13516.0): selecting to kill, queued 0, seq 6, exc 8071 0 goal 8071 0... Apr 20 20:07:14 EL135 kernel: kill_signal(13516.0): task d7294050, thg c03f42c0, sig 1 Apr 20 20:07:14 EL135 kernel: kill_signal(13516.0): selected 1, signalled 1, queued 1, seq 6, exc 8071 0 red 189481 331 Apr 20 20:07:14 EL135 kernel: kill_signal(13516.0): task d7294050, thg c03f42c0, sig 2 Watchdog is a watchdog task, that was idle; nothing in the logs to suggest it had done anything for days. Its job is to restart one of the applications if it dies, so a bit ironic that it is the first to get killed. Tail was monitoring a few logs files. Unlikely to be consuming memory madly. The apache web-server only serves pages to a little old lady who only uses it to get to church on Sundays a couple of developers who were in bed asleep, and hadn't visited a page on the site for a few weeks. The only traffic it might have had is from the port-scanners; all the content is password-protected and not linked from anywhere, so no spiders are interested. Python is running two separate custom applications. Nothing in the logs to suggest they weren't humming along as normal. One of them was a relatively recent implementation, which makes suspect #1. It doesn't have any data-structures of any significance, and normally uses only about 8% of the total physical RAW. It hasn't misbehaved since. The grep is suspect #2, and the one I want to be guilty, because it was a once-off command. The command (which piped the output of a grep -r to another grep) had been started at least 30 minutes earlier, and the fact it was still running is suspicious. However, I wouldn't have thought grep would ever use a significant amount of memory. It took a while for the OOM killer to get to it, which suggests it wasn't going mad, but the OOM killer stopped once it was killed, suggesting it may have been a memory-hog that finally satisfied the OOM killer's blood-lust.

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  • Confusion about TCP packet analysis terms

    - by Berkay
    I'm analyzing our network and have some confusion about the terms: this is the 2-packet output from source to destination. from these i have to get some features as describe, pls make me clear... packets with at least a bytes of TCP data payload: it seems tcp.len0; The minimum segment size (confusion is headers are included or or not) The average segment size observed during the lifetime of the connection, the definition: is calculated as the value reported in the actual data bytes divided by the actual data pkts reported. Total bytes in IP packets, should be ip_len value. Total bytes in (Ethernet) The total number of bytes sent probably related to frame.len and frame.cap_len these two terms are describes as, also make me clear about these two terms. frame.cap_len: Frame length stored into the capture file frame.len: Frame length on the wire

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  • Windows Disk I/O Analysis

    - by Jonathon
    It appears that we are having a problem with the disk i/o speed on our Windows 2003 Enterprise Edition server (64-bit). As we were initializing a database that created two 1G tablespaces on 3 different machines, it became obvious that the two smaller machines (each 32-bit Windows 2003 Standard Edition with less RAM) killed the larger machine when creating the files. The larger machine took 10x as long to create the tablespaces than did the other machines. Now, I am left wondering how that could be. What programs or scripts would you guys recommend for tracking down the I/O problem? I think the issue may be with the controller card (all boxes are hardware RAID 10, but have different controller cards), but I would like to check the actual disk I/O speed as well, so I have some hard numbers to work with. Any help would be appreciated.

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  • Ubuntu 12.04 crash analysis - strange binary data on all open files at the moment of crash

    - by lanbo
    A couple of hours ago we got a system crash on Ubuntu 12.04. We checked all the log files and there is nothing suspicious to blame to. Last stuff that was logged was some dovecot activity. There are no kernel panic messages. Nothing. It is a new server (new hardware) we are testing before production. And because it is new hard, I'm suspicious the problem may be due to some faulty hardware. We already run memtester with no problem detected. I'll be happy to hear from other hardware testing tools (the machine has SSD). Anyway, the thing I wanted to ask you is a different one. The strange thing is on every open file at the moment of the crash we found the next sequence of symbols was written into them: "@^@^@^@^@^@^@...". For example, on the syslog log file we got: Apr 16 15:53:56 odyssey dovecot: pop3-login: Aborted login (auth failed, 1 attempts): user=<info>, method=PLAIN, rip=46.29.255.73, lip=5.9.58.177 ^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^ [these continues for about 1000 chars...] ^@^@^@^@Apr 16 15:55:12 odyssey kernel: imklog 5.8.6, log source = /proc/kmsg started. We got all these symbols in all open files. These include: syslog, mail.log, kern.log, ... But also on some logs that are output by php scripts run in CRONs from user accounts (not root). So, any idea why all open files got these characters written during the crash? This is pretty bad since the crash corrupted many files (we don't even know which other ones may be affected). We are suspicious that all open files (in write mode maybe) at the moment of the crash got all these symbols inserted. Why is that? BTW [in case it helps], the system automatically rebooted after the crash but Apache did not start. There were not traces in /var/apache2/*log why apache did not start. After running a "service apache2 start" it started with no problems. Also, we rebooted the machine manually and Apache also started on reboot. But it did not start after the crash and no errors were reported. Thanks guys!

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  • WordPress-based ticketing systems?

    - by CarlF
    I have been asked to set up a ticketing/help desk system for a small nonprofit. Our server runs Debian GNU/Linux. Because we already have WordPress installed and plan to exploit it heavily going forward, I'm wondering whether there are any WP-based ticketing systems. Obviously, it will simplify the admin's life to have less software installed on the server. Thanks.

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  • Better way to quad+ boot operating systems?

    - by Wijagels
    I currently have Windows 7, Ubuntu 12.04, Fedora 17, and open SUSE installed. I currently use BURG boot loader to load up all the systems. However, BURG does not work with windows(I still manage) and it is a little finicky. So, I want to make windows work and have all the other OSes I want all on one boot loader. I already tried easy BCD and for whatever reason Fedora took over and blocked out the other OSes.

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