Philipp Claßen's questions

I have a (formerly working) logrotate setup for OpenResty that I took from a previous Ubuntu 18.04 installation. Yet the logrotate.service fails with this error now ...

error: error renaming /usr/local/openresty/nginx/logs/access.log.60.zst
to /usr/local/openresty/nginx/logs/access.log.61.zst: Read-only file system

... and I have difficulties understanding why. The new machines are running Ubuntu 20.04, but I don't see why that should make a difference in this case.

First, here is the config:

$ cat /etc/logrotate.d/custom-openresty

/usr/local/openresty/nginx/logs/access.log
/usr/local/openresty/nginx/logs/error.log
{
  daily
  rotate 60
  maxsize 1G
  missingok
  notifempty
  compress
  compresscmd /usr/bin/zstd
  uncompresscmd /usr/bin/unzstd
  compressoptions -9 --long -T1
  compressext .zst
  delaycompress
  sharedscripts
  postrotate
    test ! -f /usr/local/openresty/nginx/logs/nginx.pid || kill -USR1 `cat /usr/local/openresty/nginx/logs/nginx.pid`
 endscript
}

/etc/logrotate.conf is unchanged and looks like this:

# see "man logrotate" for details
# rotate log files weekly
weekly

# use the adm group by default, since this is the owning group
# of /var/log/syslog.
su root adm

# keep 4 weeks worth of backlogs
rotate 4

# create new (empty) log files after rotating old ones
create

# use date as a suffix of the rotated file
#dateext

# uncomment this if you want your log files compressed
#compress

# packages drop log rotation information into this directory
include /etc/logrotate.d

# system-specific logs may be also be configured here.

Here is the state of my files (I would expect to get access.log.1 after logrotate ran):

$ ls -alhg /usr/local/openresty/nginx/logs/
total 10G
drwxr-xr-x  2 root 4.0K Sep 16 20:04 .
drwxr-xr-x 18 root 4.0K Sep 16 19:42 ..
-rw-r--r--  1 root  10G Sep 16 19:56 access.log
-rw-r--r--  1 root 5.5K Sep 16 19:56 error.log

However, the logrotate.service fails with this error:

~$ systemctl status logrotate.service 
● logrotate.service - Rotate log files
     Loaded: loaded (/lib/systemd/system/logrotate.service; static; vendor preset: enabled)
     Active: failed (Result: exit-code) since Wed 2020-09-16 20:11:32 UTC; 4min 32s ago
TriggeredBy: ● logrotate.timer
       Docs: man:logrotate(8)
             man:logrotate.conf(5)
    Process: 27403 ExecStart=/usr/sbin/logrotate /etc/logrotate.conf (code=exited, status=1/FAILURE)
   Main PID: 27403 (code=exited, status=1/FAILURE)

$ sudo journalctl --unit logrotate.service

Sep 16 20:11:32 fetcher-scheduler systemd[1]: Starting Rotate log files...
Sep 16 20:11:32 fetcher-scheduler logrotate[27403]: error: error renaming /usr/local/openresty/nginx/logs/access.log.60.zst to /usr/local/openresty/nginx/logs/access.log.61.zst: Read-only file system
Sep 16 20:11:32 fetcher-scheduler systemd[1]: logrotate.service: Main process exited, code=exited, status=1/FAILURE
Sep 16 20:11:32 fetcher-scheduler systemd[1]: logrotate.service: Failed with result 'exit-code'.
Sep 16 20:11:32 fetcher-scheduler systemd[1]: Failed to start Rotate log files.

When I run it (without systemd) in debug mode as root, I get the following output:

# logrotate -v -d /etc/logrotate.d/custom-openresty

reading config file /etc/logrotate.d/custom-openresty
compress_prog is now /usr/bin/zstd
uncompress_prog is now /usr/bin/unzstd
compress_options is now  -9 --long -T1
compress_ext is now .zst
Reading state from file: /var/lib/logrotate/status
Allocating hash table for state file, size 64 entries
Creating new state
Creating new state
...
Creating new state

Handling 1 logs

rotating pattern: /usr/local/openresty/nginx/logs/access.log
/usr/local/openresty/nginx/logs/error.log
 after 1 days (60 rotations)
empty log files are not rotated, log files >= 1073741824 are rotated earlier, old logs are removed
considering log /usr/local/openresty/nginx/logs/access.log
  Now: 2020-09-16 20:24
  Last rotated at 2020-09-16 20:11
  log needs rotating
considering log /usr/local/openresty/nginx/logs/error.log
  Now: 2020-09-16 20:24
  Last rotated at 2020-09-16 19:00
  log does not need rotating (log has been rotated at 2020-9-16 19:0, that is not day ago yet)
rotating log /usr/local/openresty/nginx/logs/access.log, log->rotateCount is 60
dateext suffix '-20200916'
glob pattern '-[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]'
previous log /usr/local/openresty/nginx/logs/access.log.1 does not exist
renaming /usr/local/openresty/nginx/logs/access.log.60.zst to /usr/local/openresty/nginx/logs/access.log.61.zst (rotatecount 60, logstart 1, i 60), 
renaming /usr/local/openresty/nginx/logs/access.log.59.zst to /usr/local/openresty/nginx/logs/access.log.60.zst (rotatecount 60, logstart 1, i 59), 
...
/logs/access.log.3.zst (rotatecount 60, logstart 1, i 2), 
renaming /usr/local/openresty/nginx/logs/access.log.1.zst to /usr/local/openresty/nginx/logs/access.log.2.zst (rotatecount 60, logstart 1, i 1), 
renaming /usr/local/openresty/nginx/logs/access.log.0.zst to /usr/local/openresty/nginx/logs/access.log.1.zst (rotatecount 60, logstart 1, i 0), 
log /usr/local/openresty/nginx/logs/access.log.61.zst doesn't exist -- won't try to dispose of it
renaming /usr/local/openresty/nginx/logs/access.log to /usr/local/openresty/nginx/logs/access.log.1
running postrotate script
running script with arg /usr/local/openresty/nginx/logs/access.log
/usr/local/openresty/nginx/logs/error.log
: "
    test ! -f /usr/local/openresty/nginx/logs/nginx.pid || kill -USR1 `cat /usr/local/openresty/nginx/logs/nginx.pid`
"

To me, everything looks normal. If I run it, it also works:

# logrotate -v /etc/logrotate.d/custom-openresty
reading config file /etc/logrotate.d/custom-openresty
compress_prog is now /usr/bin/zstd
uncompress_prog is now /usr/bin/unzstd
compress_options is now  -9 --long -T1
compress_ext is now .zst
Reading state from file: /var/lib/logrotate/status
Allocating hash table for state file, size 64 entries
Creating new state
...
Creating new state

Handling 1 logs

rotating pattern: /usr/local/openresty/nginx/logs/access.log
/usr/local/openresty/nginx/logs/error.log
 after 1 days (60 rotations)
empty log files are not rotated, log files >= 1073741824 are rotated earlier, old logs are removed
considering log /usr/local/openresty/nginx/logs/access.log
  Now: 2020-09-16 20:26
  Last rotated at 2020-09-16 20:11
  log needs rotating
considering log /usr/local/openresty/nginx/logs/error.log
  Now: 2020-09-16 20:26
  Last rotated at 2020-09-16 19:00
  log does not need rotating (log has been rotated at 2020-9-16 19:0, that is not day ago yet)
rotating log /usr/local/openresty/nginx/logs/access.log, log->rotateCount is 60
dateext suffix '-20200916'
glob pattern '-[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]'
previous log /usr/local/openresty/nginx/logs/access.log.1 does not exist
renaming /usr/local/openresty/nginx/logs/access.log.60.zst to /usr/local/openresty/nginx/logs/access.log.61.zst (rotatecount 60, logstart 1, i 60), 
old log /usr/local/openresty/nginx/logs/access.log.60.zst does not exist
...
old log /usr/local/openresty/nginx/logs/access.log.2.zst does not exist
renaming /usr/local/openresty/nginx/logs/access.log.1.zst to /usr/local/openresty/nginx/logs/access.log.2.zst (rotatecount 60, logstart 1, i 1), 
old log /usr/local/openresty/nginx/logs/access.log.1.zst does not exist
renaming /usr/local/openresty/nginx/logs/access.log.0.zst to /usr/local/openresty/nginx/logs/access.log.1.zst (rotatecount 60, logstart 1, i 0), 
old log /usr/local/openresty/nginx/logs/access.log.0.zst does not exist
log /usr/local/openresty/nginx/logs/access.log.61.zst doesn't exist -- won't try to dispose of it
renaming /usr/local/openresty/nginx/logs/access.log to /usr/local/openresty/nginx/logs/access.log.1
running postrotate script

No error and in the end access.log.1 is created as expected:

# ls -algh /usr/local/openresty/nginx/logs/
total 10G
drwxr-xr-x  2 root 4.0K Sep 16 20:26 .
drwxr-xr-x 18 root 4.0K Sep 16 19:42 ..
-rw-r--r--  1 root  10G Sep 16 19:56 access.log.1
-rw-r--r--  1 root 5.5K Sep 16 19:56 error.log

Note that it said ...

log /usr/local/openresty/nginx/logs/access.log.61.zst
doesn't exist -- won't try to dispose of it

... instead of error renaming ... Read-only file system (as logrotate.service does)

Why does it work when running manually as root, but fails when it is executed by the logrotate.service?

I did not make any changes to logrotate.service. For completeness, here is the unit file:

$ systemctl cat logrotate.service
# /lib/systemd/system/logrotate.service
[Unit]
Description=Rotate log files
Documentation=man:logrotate(8) man:logrotate.conf(5)
ConditionACPower=true

[Service]
Type=oneshot
ExecStart=/usr/sbin/logrotate /etc/logrotate.conf

# performance options
Nice=19
IOSchedulingClass=best-effort
IOSchedulingPriority=7

# hardening options
#  details: https://www.freedesktop.org/software/systemd/man/systemd.exec.html
#  no ProtectHome for userdir logs
#  no PrivateNetwork for mail deliviery
#  no ProtectKernelTunables for working SELinux with systemd older than 235
#  no MemoryDenyWriteExecute for gzip on i686
PrivateDevices=true
PrivateTmp=true
ProtectControlGroups=true
ProtectKernelModules=true
ProtectSystem=full
RestrictRealtime=true

Now I'm running out of options. Any help in troubleshooting the problem is much appreciated.

I noticed these error messages in the systemd logs on all our AWS servers running Ubuntu (on both 16.04 and 18.04):

dev-xvdb.device: Job dev-xvdb.device/start timed out.
Timed out waiting for device dev-xvdb.device.
Dependency failed for /mnt.
mnt.mount: Job mnt.mount/start failed with result 'dependency'.
Dependency failed for File System Check on /dev/xvdb.
[email protected]: Job [email protected]/start failed with result 'dependency'.
dev-xvdb.device: Job dev-xvdb.device/start failed with result 'timeout'.

The functionality of the servers is not affected as far as I can see. The messages are always the same, start appearing at startup and repeat every few hours, although there is no clear pattern:

Jul 24 20:13:50
Jul 25 00:05:19
Jul 25 06:09:19
Jul 25 12:32:19
Jul 25 13:13:08
Jul 25 19:19:49
Jul 26 01:31:09
Jul 26 06:11:02
Jul 26 10:09:19
Jul 26 14:05:19
Jul 26 19:09:19
...

The messages also appear on idle servers, so I do not think it is related to the current workload.

Question:

• Do you know what the error message is about?
• Can it be fixed, or is it safe to ignore it?

Additional system information:

$ cat /etc/fstab 
LABEL=cloudimg-rootfs / ext4 defaults,discard 0 0
/dev/xvdb /mnt auto defaults,nofail,x-systemd.requires=cloud-init.service,comment=cloudconfig 0 2

There are many similar named packages for libasan (the address sanitizer for gcc and clang):

$ apt-cache search libasan | grep -v dbg | grep -v cross
libasan2 - AddressSanitizer -- a fast memory error detector
libasan3 - AddressSanitizer -- a fast memory error detector
libasan4 - AddressSanitizer -- a fast memory error detector
libasan0 - AddressSanitizer -- a fast memory error detector

(Output is from Ubuntu 17.10. Ubuntu 18.04 also has libasan5.)

• What is the difference between these packages?
• Which one should I install?

Let us assume you just logged via SSH into a server running Ubuntu.

Is there a simple command to find out whether unattended-upgrades are enabled and will install security critical updates automatically?

Is it possible to run a script before the shutdown? That means at a point where the system is still fully functional.

I tried to put my shutdown script in /lib/systemd/system-shutdown/test-script. It will be executed but from my understanding it is only executed immediately before the shutdown takes place. For instance, the disk is already mounted in read-only mode. This can be fixed, but wrapping the script with:

#!/bin/bash
mount -oremount,rw /
... do something ...
mount -oremount,ro /

What I require and cannot get to work, though, is internet connection. When the script is executed, the internet connection seems to be no longer available.

Is it possible to run a script right at the begin of the shutdown protocol?

I'm testing with Ubuntu 16.04.

I want to install certbot in a docker environment with an Ubuntu 16.04 image:

For example:

docker run -it ubuntu:16.04 /bin/bash

When I'm inside the container, the most straightforward way to install certbot does not work as it requires user intervention:

apt-get update && \
apt-get install -y software-properties-common && \
add-apt-repository -y -u ppa:certbot/certbot && \
apt-get install -y certbot

The problem is tzdata, which stops with this interactive dialog:

Extracting templates from packages: 100%
Preconfiguring packages ...
Configuring tzdata
------------------

Please select the geographic area in which you live. Subsequent configuration
questions will narrow this down by presenting a list of cities, representing
the time zones in which they are located.

 1. Africa      4. Australia  7. Atlantic  10. Pacific  13. Etc
 2. America     5. Arctic     8. Europe    11. SystemV
 3. Antarctica  6. Asia       9. Indian    12. US
Geographic area: 

Strangely enough, it works when I install tzdata before adding the ppa:

apt-get update && \
apt-get install -y tzdata && \
apt-get install -y software-properties-common && \
add-apt-repository -y -u ppa:certbot/certbot && \
apt-get install -y certbot

Questions:

• Why makes it a difference whether I install tzdata before or after adding the ppa?
• Is there a better approach for avoiding the interactive dialog when installing certbot?

Steam works fine but it hangs when I apply the following steps:

1. Start steam
2. Stop steam
3. suspend my laptop
4. (after wakeup) start steam

Now the steam client hangs at startup. I only see a blank popup window without any content. I assume that should be the login popup ("Connecting to steam account").

The only workaround is to reboot my system. If I try killall steam && steam, it still hangs again at the same point.

Here is the console output:

Running Steam on ubuntu 14.10 64-bit
STEAM_RUNTIME is enabled automatically
[2015-01-02 16:06:15] Startup - updater built Nov 21 2014 16:23:41
Looks like steam didn't shutdown cleanly, scheduling immediate update check
[2015-01-02 16:06:15] Checking for update on startup
[2015-01-02 16:06:15] Checking for available updates...
[2015-01-02 16:06:16] Download skipped by HTTP 304 Not Modified
[2015-01-02 16:06:16] Nothing to do
[2015-01-02 16:06:16] Verifying installation...
[2015-01-02 16:06:16] Performing checksum verification of executable files
[2015-01-02 16:06:17] Verification complete
Requested Force create but SharedObjectMutex already created
Forced create but already created for SharedObjectEvent
Forced create but already created for SharedObjectEvent

--- here it hangs. After a reboot, it would continue like that ---

Running Steam on ubuntu 14.10 64-bit
STEAM_RUNTIME has been set by the user to: /home/phil/.steam/ubuntu12_32/steam-runtime

Here is the output of ~/.steam/error.log:

rm: cannot remove ‘/home/phil/.steam/steam’: Is a directory
rm: cannot remove ‘/home/phil/.steam/bin’: Is a directory
Installing breakpad exception handler for appid(steam)/version(1416617579)
Installing breakpad exception handler for appid(steam)/version(1416617579)
Gtk-Message: Failed to load module "overlay-scrollbar"
Gtk-Message: Failed to load module "overlay-scrollbar"
Installing breakpad exception handler for appid(steamwebhelper)/version(20141121162341)
Installing breakpad exception handler for appid(steamwebhelper)/version(1416587021)
Installing breakpad exception handler for appid(steamwebhelper)/version(1416587021)
Installing breakpad exception handler for appid(steamwebhelper)/version(20141121162341)
Installing breakpad exception handler for appid(steamwebhelper)/version(1416587021)
[0102/162746:ERROR:nss_util.cc(1018)] Failed to load NSS libraries.
Installing breakpad exception handler for appid(steam)/version(1416617579)
Fontconfig error: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 70: non-double matrix element
Fontconfig error: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 70: non-double matrix element
Fontconfig warning: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 78: saw unknown, expected number
Installing breakpad exception handler for appid(steam)/version(1416617579)
Installing breakpad exception handler for appid(steam)/version(1416617579)
Installing breakpad exception handler for appid(steam)/version(1416617579)
Installing breakpad exception handler for appid(steam)/version(1416617579)
Installing breakpad exception handler for appid(steam)/version(1416617579)
FillInMachineIDInfo took a total of 0 milliseconds
Installing breakpad exception handler for appid(steam)/version(1416617579)
Installing breakpad exception handler for appid(steam)/version(1416617579)
Installing breakpad exception handler for appid(steam)/version(1416617579)
Generating new string page texture 2: 48x256, total string texture memory is 49,15 KB
Generating new string page texture 3: 256x256, total string texture memory is 311,30 KB

I tried several recommended workarounds, for example:

• killall steam && rm ~/.steam/steam/appcache
• mv /etc/fonts/conf.d/10-scale-bitmap-fonts.conf{,.BAK}

However, only a reboot fixes the start problem.

I'm using Ubuntu 14.10 (64-bit). (My window manager is i3. Don't think that is relevant but I read about issues with xmonad.)

I just upgraded from Ubuntu 12.04 to 14.04, but during the installation grub-install failed:

I continued with the installation and hoped to fix the grub issue afterwards. However, I ran into some difficulties. I have not restarted my system, as I fear that it will not be able to reboot.

This is the error that I always get trying to install grub:

 $ sudo grub-install /dev/mapper/isw_cjccfdbihf_Volume0p1 
 Installing for i386-pc platform.
 grub-install: error: cannot find a GRUB drive for /dev/mapper/isw_cjccfdbihf_Volume0p1.  Check your device.map.

(I also tried sudo grub-install /dev/sda but it also fails with the exact same error messsage.)

The machine seems to use a RAID 1 setup. Here are some information:

$ ls -algh /dev/mapper/
total 0
drwxr-xr-x  2 root     120 Aug 12 19:41 .
drwxr-xr-x 16 root    5.2K Aug 12 20:27 ..
crw-------  1 root 10, 236 Jul 28 10:30 control
lrwxrwxrwx  1 root       7 Aug 12 19:41 isw_cjccfdbihf_Volume0p1 -> ../dm-1
lrwxrwxrwx  1 root       7 Aug 12 19:41 isw_cjccfdbihf_Volume0p2 -> ../dm-2
lrwxrwxrwx  1 root       7 Aug 12 19:41 isw_cjccfdbihf_Volume0p5 -> ../dm-3

$ sudo grub-probe -t device /boot/grub
/dev/mapper/isw_cjccfdbihf_Volume0p1

$ sudo fdisk -l

Disk /dev/sda: 250.1 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders, total 488397168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0003b681

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1            2048   468514815   234256384   83  Linux
/dev/sda2       468516862   488390655     9936897    5  Extended
/dev/sda5       468516864   488390655     9936896   82  Linux swap / Solaris

Disk /dev/sdb: 250.1 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders, total 488397168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0003b681

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1            2048   468514815   234256384   83  Linux
/dev/sdb2       468516862   488390655     9936897    5  Extended
/dev/sdb5       468516864   488390655     9936896   82  Linux swap / Solaris

Disk /dev/mapper/isw_cjccfdbihf_Volume0p1: 239.9 GB, 239878537216 bytes
255 heads, 63 sectors/track, 29163 cylinders, total 468512768 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

Disk /dev/mapper/isw_cjccfdbihf_Volume0p1 doesn't contain a valid partition table
fdisk: unable to read /dev/mapper/isw_cjccfdbihf_Volume0p2: Inappropriate ioctl for device

Especially, the last two lines seem to indicate a deeper problem. :-(

The error message of grub-install also mentions a device.map file.

$ cat /boot/grub/device.map
cat: /boot/grub/device.map: No such file or directory

I tried to generate it but it did not help either (the error message did not change):

$ sudo grub-mkdevicemap
$ cat /boot/grub/device.map
 (hd0)  /dev/disk/by-id/ata-WDC_WD2500AAJS-00YZCA0_WD-WCAYU7549707
 (hd1)  /dev/disk/by-id/ata-WDC_WD2500AAJS-00YZCA0_WD-WCAYU7501473

Do you have any recommendations what I should try out next? Any help is deeply appreciated.

Update:

$ debconf-show grub-pc
debconf: DbDriver "passwords" warning: could not open /var/cache/debconf    /passwords.dat: Permission denied
* grub-pc/install_devices: /dev/disk/by-id/dm-name-isw_cjccfdbihf_Volume0
  grub-pc/kopt_extracted: false
  grub-pc/partition_description:
* grub2/linux_cmdline:
  grub-pc/install_devices_empty: false
  grub-pc/timeout: 10
  grub-pc/install_devices_failed_upgrade: true
* grub2/linux_cmdline_default: quiet splash
  grub-pc/postrm_purge_boot_grub: false
  grub-pc/hidden_timeout: true
  grub-pc/disk_description:
  grub-pc/mixed_legacy_and_grub2: true
  grub2/kfreebsd_cmdline_default: quiet splash
  grub2/device_map_regenerated:
* grub-pc/install_devices_failed: true
  grub-pc/chainload_from_menu.lst: true
  grub-pc/install_devices_disks_changed:
  grub2/kfreebsd_cmdline:

Note the line: grub-pc/install_devices: /dev/disk/by-id/dm-name-isw_cjccfdbihf_Volume0

Now the content of /etc/fstab:

proc            /proc           proc    nodev,noexec,nosuid 0       0
/dev/mapper/isw_cjccfdbihf_Volume01 /               ext4    errors=remount-ro 0       1
/dev/mapper/isw_cjccfdbihf_Volume0p5 none            swap    sw              0       0

An backup file from 2012 shows slightly different entries for swap (Volume05 instead of Volume0p5), which indicates that the names could have been changed:

 # Note that this is an old file at the time the system was installed (Ubuntu 10.04 or 10.10)
 # (This is also the time from which the original grub configuration is from, isn't it?!)
 /dev/mapper/isw_cjccfdbihf_Volume01 /               ext4    errors=remount-ro 0       1
 /dev/mapper/isw_cjccfdbihf_Volume05 none            swap    sw              0       0

So, maybe it has something to do with "_Volume01" vs "_Volume0p1" vs "_Volume0". /etc/fstab says "01", ls /dev/mapper returns mappings "0p1", "0p2" and "0p5" (swap), and finally debconf-show grub-pc says "Volume0". I think this inconsistency is the root of the problem.

Now I wonder:

1. What should the line grub-pc/install_devices in the output of debconf-show grub-pc be?
2. How can I change the Grub settings, so I can experiment with different values?

I also just noticed that the installation of grub-pc is broken:

$ sudo dpkg-reconfigure grub-pc
/usr/sbin/dpkg-reconfigure: grub-pc is broken or not fully installed

sudo apt-get update sometimes becomes stucked:

...
99% [Waiting for headers]

This seems to be a common problem and can have several reasons. For example, on one machine, it was caused because I used a bad proxy server configuration.

Is there a way to systematically analyze the problem? It looked at the man apt-get but could not find any option that provides more information to isolate the problem. Are there any tools besides apt-get that I can use to get more insights?