Search Results

Search found 2995 results on 120 pages for 'logical operators'.

Page 4/120 | < Previous Page | 1 2 3 4 5 6 7 8 9 10 11 12  | Next Page >

  • No device file for partition on logical volume (Linux LVM)

    - by Brian
    I created a logical volume (scandata) containing a single ext3 partition. It is the only logical volume in its volume group (case4t). Said volume group is comprised by 3 physical volumes, which are three primary partitions on a single block device (/dev/sdb). When I created it, I could mount the partition via the block device /dev/mapper/case4t-scandatap1. Since last reboot the aforementioned block device file has disappeared. It may be of note -- I'm not sure -- that my superior (a college professor) had prompted this reboot by running sudo chmod -R [his name] /usr/bin, which obliterated all suid in its path, preventing the both of us from sudo-ing. That issue has been (temporarily) rectified via this operation. Now I'll cut the chatter and get started with the terminal dumps: $ sudo pvs; sudo vgs; sudo lvs Logging initialised at Sat Jan 8 11:42:34 2011 Set umask to 0077 Scanning for physical volume names PV VG Fmt Attr PSize PFree /dev/sdb1 case4t lvm2 a- 819.32G 0 /dev/sdb2 case4t lvm2 a- 866.40G 0 /dev/sdb3 case4t lvm2 a- 47.09G 0 Wiping internal VG cache Logging initialised at Sat Jan 8 11:42:34 2011 Set umask to 0077 Finding all volume groups Finding volume group "case4t" VG #PV #LV #SN Attr VSize VFree case4t 3 1 0 wz--n- 1.69T 0 Wiping internal VG cache Logging initialised at Sat Jan 8 11:42:34 2011 Set umask to 0077 Finding all logical volumes LV VG Attr LSize Origin Snap% Move Log Copy% Convert scandata case4t -wi-a- 1.69T Wiping internal VG cache $ sudo vgchange -a y Logging initialised at Sat Jan 8 11:43:14 2011 Set umask to 0077 Finding all volume groups Finding volume group "case4t" 1 logical volume(s) in volume group "case4t" already active 1 existing logical volume(s) in volume group "case4t" monitored Found volume group "case4t" Activated logical volumes in volume group "case4t" 1 logical volume(s) in volume group "case4t" now active Wiping internal VG cache $ ls /dev | grep case4t case4t $ ls /dev/mapper case4t-scandata control $ sudo fdisk -l /dev/case4t/scandata Disk /dev/case4t/scandata: 1860.5 GB, 1860584865792 bytes 255 heads, 63 sectors/track, 226203 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x00049bf5 Device Boot Start End Blocks Id System /dev/case4t/scandata1 1 226203 1816975566 83 Linux $ sudo parted /dev/case4t/scandata print Model: Linux device-mapper (linear) (dm) Disk /dev/mapper/case4t-scandata: 1861GB Sector size (logical/physical): 512B/512B Partition Table: msdos Number Start End Size Type File system Flags 1 32.3kB 1861GB 1861GB primary ext3 $ sudo fdisk -l /dev/sdb Disk /dev/sdb: 1860.5 GB, 1860593254400 bytes 255 heads, 63 sectors/track, 226204 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x00000081 Device Boot Start End Blocks Id System /dev/sdb1 1 106955 859116006 83 Linux /dev/sdb2 113103 226204 908491815 83 Linux /dev/sdb3 106956 113102 49375777+ 83 Linux Partition table entries are not in disk order $ sudo parted /dev/sdb print Model: DELL PERC 6/i (scsi) Disk /dev/sdb: 1861GB Sector size (logical/physical): 512B/512B Partition Table: msdos Number Start End Size Type File system Flags 1 32.3kB 880GB 880GB primary reiserfs 3 880GB 930GB 50.6GB primary 2 930GB 1861GB 930GB primary I find it a bit strange that partition one above is said to be reiserfs, or if it matters -- it was previously reiserfs, but LVM recognizes it as a PV. To reiterate, neither /dev/mapper/case4t-scandatap1 (which I had used previously) nor /dev/case4t/scandata1 (as printed by fdisk) exists. And /dev/case4t/scandata (no partition number) cannot be mounted: $sudo mount -t ext3 /dev/case4t/scandata /mnt/new mount: wrong fs type, bad option, bad superblock on /dev/mapper/case4t-scandata, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or so All I get on syslog is: [170059.538137] VFS: Can't find ext3 filesystem on dev dm-0. Thanks in advance for any help you can offer, Brian P.S. I am on Ubuntu GNU/Linux 2.6.28-11-server (Jaunty) (out of date, I know -- that's on the laundry list).

    Read the article

  • The EXCEPT and INTERSECT Operators in SQL Server

    The UNION, EXCEPT and INTERSECT operators of SQL enable you to combine more than one SELECT statement to form a single result set. Rob Sheldon explains all, with plenty of examples. Join SQL Backup’s 35,000+ customers to compress and strengthen your backups "SQL Backup will be a REAL boost to any DBA lucky enough to use it." Jonathan Allen. Download a free trial now.

    Read the article

  • Bringing Alerts and Operators together with Notifications

    - by fatherjack
    I have covered SQL Server Alerts (Alerts are good, arent they?) on this blog before and I more recently did a post regarding Notifications (Are your Jobs talking to you) and how they should be configured. Now we need to check that these things are linked up so that when an Alert condition is met that you get the appropriate Notifications sent to Operators. Straight into the code we need and then a review of what it does ... DECLARE @ChosenOperator SYSNAME DECLARE @FailSafeOp TABLE ...(read more)

    Read the article

  • Query Performance Degrades with High Number of Logical Reads

    - by electricsk8
    I'm using Confio Ignite8 to derive this information, and monitor waits. I have one query that runs frequently, and I notice that on some days there is an extremely high number of logical reads incurred, +300,000,000 for 91,000 executions. On a good day, the logical reads are much lower, 18,000,000 for 94,000 executions. The execution plan for the query utilizes clustered index seeks, and is below. StmtText |--Nested Loops(Inner Join, OUTER REFERENCES:([f].[ParentId])) |--Clustered Index Seek(OBJECT:([StructuredFN].[dbo].[Folder].[PK_Folders] AS [f]), SEEK:([f].[FolderId]=(8125)), WHERE:([StructuredFN].[dbo].[Folder].[DealId] as [f].[DealId]=(300)) ORDERED FORWARD) |--Clustered Index Seek(OBJECT:([StructuredFN].[dbo].[Folder].[PK_Folders] AS [p]), SEEK:([p].[FolderId]=[StructuredFN].[dbo].[Folder].[ParentId] as [f].[ParentId]), WHERE:([StructuredFN].[dbo].[Folder].[DealId] as [p].[DealId]=(300)) ORDERED FORWARD) Output from showstatistics io ... Table 'Folder'. Scan count 0, logical reads 4, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0. Any ideas on how to troubleshoot where these high logical reads come from on certain days, and others nothing?

    Read the article

  • Kernel panic on reboot after failed logical volume resize

    - by Derek
    I attempted to do a logical volume resize yesterday using the follwoing commands $sudo pvdisplay "/dev/sda8" is a new physical volume of "113.11 GiB" --- NEW Physical volume --- PV Name /dev/sda8 VG Name PV Size 113.11 GiB Allocatable NO PE Size 0 Total PE 0 Free PE 0 Allocated PE 0 PV UUID jwyO1o-b2ap-CW51-kx7O-kf26-arim-SM8V6m $sudo vgextend vg /dev/sda8 sudo vgdisplay vg --- Volume group --- VG Name vg System ID Format lvm2 Metadata Areas 2 Metadata Sequence No 9 VG Access read/write VG Status resizable MAX LV 0 Cur LV 5 Open LV 5 Max PV 0 Cur PV 2 Act PV 2 VG Size 131.74 GiB PE Size 4.00 MiB Total PE 33725 Alloc PE / Size 4769 / 18.63 GiB Free PE / Size 28956 / 113.11 GiB VG UUID AhusW2-pzFv-3W32-mpv2-s5VG-FN7S-kVSadx $sudo lvresize -L +20GB /dev/mapper/vg-var So as you can see, it looks like adding the physical volume to the vg worked, because i see free space available there. When I typed the lvresize command, it never returned. I let this run overnight in the background, but this morning I still couldnt successfully do a "pvdisplay" or "lvdisplay" because I think it was waiting on a lock or something, so the command never returned. When i went to log onto the server's console, I saw a bunch of messages like: rcu_sched_state detected stall on cpu 2 Now when I boot, I get a kernel panic error, and a message about not being able to mount /mapper/vg-root cannot open root device "mapper/vg-root" or unknown_block(0,0) Kernel Panic -not syncing: VFS: Unable to mount root file system on unknown_block(0,0) What should I do to get my system back up and running? Did I attempt to do the logical volume resize correctly? Thanks

    Read the article

  • Am I running out of memory or do I have two logical drives instead of one

    - by user30904
    I did a complete reinstall of Ubuntu 13.04 a couple of months ago. Since then, I have switched out my motherboard with another. I kept the same hard drive. I just did an upgrade to 13.10. Recently, after this install, I keep getting the message that I'm running out of memory. I just checked my system usage and was surprised by what I found. I believed that I installed Ubuntu as a fresh install but when I check the system usage, it seems like there are two logical drives. I just did the basic install, so I was only expecting to see one partition but instead I see two. One is a small 300mb partition, the other is a 300gb partition I was expecting. Can anyone tell me if I have two partitions and/or logical drives and if so how I can fix this? I seem to have been running on the smaller drive and now I'm obviously out of space. I want to be able to use the bigger one at least.

    Read the article

  • What is the justification for Python's power operator associating to the right?

    - by Pieter Müller
    I am writing code to parse mathematical expression strings, and noticed that the order in which chained power operators are evaluated in Python differs from the order in Excel. From http://docs.python.org/reference/expressions.html: "Thus, in an unparenthesized sequence of power and unary operators, the operators are evaluated from right to left (this does not constrain the evaluation order for the operands): -1*2 results in -1."* This means that, in Python: 2**2**3 is evaluated as 2**(2**3) = 2**8 = 256 In Excel, it works the other way around: 2^2^3 is evaluated as (2^2)^3 = 4^3 = 64 I now have to choose an implementation for my own parser. The Excel order is easier to implement, as it mirrors the evaluation order of multiplication. I asked some people around the office what their gut feel was for the evaluation of 2^2^3 and got mixed responses. Does anybody know of any good reasons or conciderations in favour of the Python implementation? And if you don't have an answer, please comment with the result you get from gut feel - 64 or 256?

    Read the article

  • Get Your Logical Fallacies Straight with this Rhetological Fallacies Chart

    - by Jason Fitzpatrick
    Have trouble telling your Ad Hocs from your Ad Hominems? Fear not, this extensive and easy to read logical fallacy chart makes it easy to tell when someone is begging the question or suffering from a confirmation bias. Rhetological Fallacies Chart [via Neatorama] How to Own Your Own Website (Even If You Can’t Build One) Pt 2 How to Own Your Own Website (Even If You Can’t Build One) Pt 1 What’s the Difference Between Sleep and Hibernate in Windows?

    Read the article

  • Arguments for or against using Try/Catch as logical operators

    - by James P. Wright
    I just discovered some lovely code in our companies app that uses Try-Catch blocks as logical operators. Meaning, "do some code, if that throws this error, do this code, but if that throws this error do this 3rd thing instead". It uses "Finally" as the "else" statement it appears. I know that this is wrong inherently, but before I go picking a fight I was hoping for some well thought out arguments. And hey, if you have arguments FOR the use of Try-Catch in this manner, please do tell. EDIT For any who are wondering, the language is C# and the code in question is about 30+ lines and is looking for specific exceptions, it is not handling ALL exceptions.

    Read the article

  • Implementing comparision operators via 'tuple' and 'tie', a good idea?

    - by Xeo
    (Note: tuple and tie can be taken from Boost or C++11.) When writing small structs with only two elements, I sometimes tend to choose a std::pair, as all important stuff is already done for that datatype, like operator< for strict-weak-ordering. The downsides though are the pretty much useless variable names. Even if I myself created that typedef, I won't remember 2 days later what first and what second exactly was, especially if they are both of the same type. This gets even worse for more than two members, as nesting pairs pretty much sucks. The other option for that is a tuple, either from Boost or C++11, but that doesn't really look any nicer and clearer. So I go back to writing the structs myself, including any needed comparision operators. Since especially the operator< can be quite cumbersome, I thought of circumventing this whole mess by just relying on the operations defined for tuple: Example of operator<, e.g. for strict-weak-ordering: bool operator<(MyStruct const& lhs, MyStruct const& rhs){ return std::tie(lhs.one_member, lhs.another, lhs.yet_more) < std::tie(rhs.one_member, rhs.another, rhs.yet_more); } (tie makes a tuple of T& references from the passed arguments.) Edit: The suggestion from @DeadMG to privately inherit from tuple isn't a bad one, but it got quite some drawbacks: If the operators are free-standing (possibly friends), I need to inherit publicly With casting, my functions / operators (operator= specifically) can be easily bypassed With the tie solution, I can leave out certain members if they don't matter for the ordering Are there any drawbacks in this implementation that I need to consider?

    Read the article

  • Carpool logical architecture

    - by enrmarc
    I'm designing a carpool system (drivers can publish their routes and passengers can subscribe to them) with WebServices(axis2) and Android clients (ksoap2). I have been having problems with the logical architecture of the system and I wondered if this architecture is fine. And another question: for that architecture (if it is ok), how would be the packages structure? I suppose something like that: (In android) package org.carpool.presentation *All the activities here (and maybe mvc pattern) (In the server) package org.carpool.services *Public interfaces (for example: register(User user), publishRoute(Route route) ) package org.carpool.domain *Pojos (for example: User.java, Route.java, etc) package org.carpool.persistence *Dao Interface and implementation (jdbc or hibernate)

    Read the article

< Previous Page | 1 2 3 4 5 6 7 8 9 10 11 12  | Next Page >